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-rw-r--r--drivers/i2c/Kconfig23
-rw-r--r--drivers/i2c/Makefile1
-rw-r--r--drivers/i2c/busses/i2c-aspeed.c754
-rw-r--r--drivers/i2c/i2c-core-base.c88
-rw-r--r--drivers/i2c/i2c-core-smbus.c22
-rw-r--r--drivers/i2c/i2c-mux.c112
-rw-r--r--drivers/i2c/i2c-slave-mqueue.c243
7 files changed, 1174 insertions, 69 deletions
diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
index 438905e2a1d0..339464db1df6 100644
--- a/drivers/i2c/Kconfig
+++ b/drivers/i2c/Kconfig
@@ -133,6 +133,29 @@ config I2C_SLAVE_TESTUNIT
multi-master, SMBus Host Notify, etc. Please read
Documentation/i2c/slave-testunit-backend.rst for further details.
+config I2C_SLAVE_MQUEUE_MESSAGE_SIZE
+ int "The message size of I2C mqueue slave"
+ default 120
+
+config I2C_SLAVE_MQUEUE_QUEUE_SIZE
+ int "The queue size of I2C mqueue slave"
+ default 32
+ help
+ This number MUST be power of 2.
+
+config I2C_SLAVE_MQUEUE
+ tristate "I2C mqueue (message queue) slave driver"
+ help
+ Some protocols over I2C are designed for bi-directional transferring
+ messages by using I2C Master Write protocol. This driver is used to
+ receive and queue messages from the remote I2C device.
+
+ Userspace can get the messages by reading sysfs file that this driver
+ exposes.
+
+ This support is also available as a module. If so, the module will be
+ called i2c-slave-mqueue.
+
endif
config I2C_DEBUG_CORE
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index c1d493dc9bac..0442e5cf8587 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -17,5 +17,6 @@ obj-y += algos/ busses/ muxes/
obj-$(CONFIG_I2C_STUB) += i2c-stub.o
obj-$(CONFIG_I2C_SLAVE_EEPROM) += i2c-slave-eeprom.o
obj-$(CONFIG_I2C_SLAVE_TESTUNIT) += i2c-slave-testunit.o
+obj-$(CONFIG_I2C_SLAVE_MQUEUE) += i2c-slave-mqueue.o
ccflags-$(CONFIG_I2C_DEBUG_CORE) := -DDEBUG
diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c
index 724bf30600d6..70dacc1bf4e7 100644
--- a/drivers/i2c/busses/i2c-aspeed.c
+++ b/drivers/i2c/busses/i2c-aspeed.c
@@ -7,8 +7,11 @@
* Copyright 2017 Google, Inc.
*/
+#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/completion.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmapool.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/i2c.h>
@@ -19,15 +22,24 @@
#include <linux/irqchip/chained_irq.h>
#include <linux/irqdomain.h>
#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
+#include <linux/regmap.h>
#include <linux/reset.h>
#include <linux/slab.h>
-/* I2C Register */
+/* I2C Global Registers */
+/* 0x00 : I2CG Interrupt Status Register */
+/* 0x08 : I2CG Interrupt Target Assignment */
+/* 0x0c : I2CG Global Control Register (AST2500) */
+#define ASPEED_I2CG_GLOBAL_CTRL_REG 0x0c
+#define ASPEED_I2CG_SRAM_BUFFER_EN BIT(0)
+
+/* I2C Bus Registers */
#define ASPEED_I2C_FUN_CTRL_REG 0x00
#define ASPEED_I2C_AC_TIMING_REG1 0x04
#define ASPEED_I2C_AC_TIMING_REG2 0x08
@@ -35,18 +47,20 @@
#define ASPEED_I2C_INTR_STS_REG 0x10
#define ASPEED_I2C_CMD_REG 0x14
#define ASPEED_I2C_DEV_ADDR_REG 0x18
+#define ASPEED_I2C_BUF_CTRL_REG 0x1c
#define ASPEED_I2C_BYTE_BUF_REG 0x20
-
-/* Global Register Definition */
-/* 0x00 : I2C Interrupt Status Register */
-/* 0x08 : I2C Interrupt Target Assignment */
+#define ASPEED_I2C_DMA_ADDR_REG 0x24
+#define ASPEED_I2C_DMA_LEN_REG 0x28
/* Device Register Definition */
/* 0x00 : I2CD Function Control Register */
+#define ASPEED_I2CD_BUFFER_PAGE_SEL_MASK GENMASK(22, 20)
+#define ASPEED_I2CD_BUS_AUTO_RECOVERY_EN BIT(17)
#define ASPEED_I2CD_MULTI_MASTER_DIS BIT(15)
#define ASPEED_I2CD_SDA_DRIVE_1T_EN BIT(8)
#define ASPEED_I2CD_M_SDA_DRIVE_1T_EN BIT(7)
#define ASPEED_I2CD_M_HIGH_SPEED_EN BIT(6)
+#define ASPEED_I2CD_GCALL_EN BIT(2)
#define ASPEED_I2CD_SLAVE_EN BIT(1)
#define ASPEED_I2CD_MASTER_EN BIT(0)
@@ -58,10 +72,14 @@
#define ASPEED_I2CD_TIME_SCL_HIGH_MASK GENMASK(19, 16)
#define ASPEED_I2CD_TIME_SCL_LOW_SHIFT 12
#define ASPEED_I2CD_TIME_SCL_LOW_MASK GENMASK(15, 12)
+#define ASPEED_I2CD_TIME_TIMEOUT_BASE_DIVISOR_SHIFT 8
+#define ASPEED_I2CD_TIME_TIMEOUT_BASE_DIVISOR_MASK GENMASK(9, 8)
#define ASPEED_I2CD_TIME_BASE_DIVISOR_MASK GENMASK(3, 0)
#define ASPEED_I2CD_TIME_SCL_REG_MAX GENMASK(3, 0)
+
/* 0x08 : I2CD Clock and AC Timing Control Register #2 */
-#define ASPEED_NO_TIMEOUT_CTRL 0
+#define ASPEED_I2CD_TIMEOUT_CYCLES_SHIFT 0
+#define ASPEED_I2CD_TIMEOUT_CYCLES_MASK GENMASK(4, 0)
/* 0x0c : I2CD Interrupt Control Register &
* 0x10 : I2CD Interrupt Status Register
@@ -70,8 +88,15 @@
* status bits.
*/
#define ASPEED_I2CD_INTR_RECV_MASK 0xf000ffff
+#if defined(CONFIG_MACH_ASPEED_G6)
+#define ASPEED_I2CD_INTR_SLAVE_ADDR_RECEIVED_PENDING BIT(29)
+#else
+#define ASPEED_I2CD_INTR_SLAVE_ADDR_RECEIVED_PENDING BIT(30)
+#endif
+#define ASPEED_I2CD_INTR_SLAVE_INACTIVE_TIMEOUT BIT(15)
#define ASPEED_I2CD_INTR_SDA_DL_TIMEOUT BIT(14)
#define ASPEED_I2CD_INTR_BUS_RECOVER_DONE BIT(13)
+#define ASPEED_I2CD_INTR_GCALL_ADDR BIT(8)
#define ASPEED_I2CD_INTR_SLAVE_MATCH BIT(7)
#define ASPEED_I2CD_INTR_SCL_TIMEOUT BIT(6)
#define ASPEED_I2CD_INTR_ABNORMAL BIT(5)
@@ -85,8 +110,11 @@
ASPEED_I2CD_INTR_SCL_TIMEOUT | \
ASPEED_I2CD_INTR_ABNORMAL | \
ASPEED_I2CD_INTR_ARBIT_LOSS)
+#define ASPEED_I2CD_INTR_SLAVE_ERRORS \
+ ASPEED_I2CD_INTR_SLAVE_INACTIVE_TIMEOUT
#define ASPEED_I2CD_INTR_ALL \
- (ASPEED_I2CD_INTR_SDA_DL_TIMEOUT | \
+ (ASPEED_I2CD_INTR_SLAVE_INACTIVE_TIMEOUT | \
+ ASPEED_I2CD_INTR_SDA_DL_TIMEOUT | \
ASPEED_I2CD_INTR_BUS_RECOVER_DONE | \
ASPEED_I2CD_INTR_SCL_TIMEOUT | \
ASPEED_I2CD_INTR_ABNORMAL | \
@@ -95,6 +123,11 @@
ASPEED_I2CD_INTR_RX_DONE | \
ASPEED_I2CD_INTR_TX_NAK | \
ASPEED_I2CD_INTR_TX_ACK)
+#define ASPEED_I2CD_INTR_STATUS_MASK \
+ (ASPEED_I2CD_INTR_SLAVE_ADDR_RECEIVED_PENDING | \
+ ASPEED_I2CD_INTR_GCALL_ADDR | \
+ ASPEED_I2CD_INTR_SLAVE_MATCH | \
+ ASPEED_I2CD_INTR_ALL)
/* 0x14 : I2CD Command/Status Register */
#define ASPEED_I2CD_SCL_LINE_STS BIT(18)
@@ -103,6 +136,10 @@
#define ASPEED_I2CD_BUS_RECOVER_CMD BIT(11)
/* Command Bit */
+#define ASPEED_I2CD_RX_DMA_ENABLE BIT(9)
+#define ASPEED_I2CD_TX_DMA_ENABLE BIT(8)
+#define ASPEED_I2CD_RX_BUFF_ENABLE BIT(7)
+#define ASPEED_I2CD_TX_BUFF_ENABLE BIT(6)
#define ASPEED_I2CD_M_STOP_CMD BIT(5)
#define ASPEED_I2CD_M_S_RX_CMD_LAST BIT(4)
#define ASPEED_I2CD_M_RX_CMD BIT(3)
@@ -119,6 +156,21 @@
/* 0x18 : I2CD Slave Device Address Register */
#define ASPEED_I2CD_DEV_ADDR_MASK GENMASK(6, 0)
+/* 0x1c : I2CD Buffer Control Register */
+/* Use 8-bits or 6-bits wide bit fileds to support both AST2400 and AST2500 */
+#define ASPEED_I2CD_BUF_RX_COUNT_MASK GENMASK(31, 24)
+#define ASPEED_I2CD_BUF_RX_SIZE_MASK GENMASK(23, 16)
+#define ASPEED_I2CD_BUF_TX_COUNT_MASK GENMASK(15, 8)
+#define ASPEED_I2CD_BUF_OFFSET_MASK GENMASK(5, 0)
+
+/* 0x24 : I2CD DMA Mode Buffer Address Register */
+#define ASPEED_I2CD_DMA_ADDR_MASK GENMASK(31, 2)
+#define ASPEED_I2CD_DMA_ALIGN 4
+
+/* 0x28 : I2CD DMA Transfer Length Register */
+#define ASPEED_I2CD_DMA_LEN_SHIFT 0
+#define ASPEED_I2CD_DMA_LEN_MASK GENMASK(11, 0)
+
enum aspeed_i2c_master_state {
ASPEED_I2C_MASTER_INACTIVE,
ASPEED_I2C_MASTER_PENDING,
@@ -137,6 +189,8 @@ enum aspeed_i2c_slave_state {
ASPEED_I2C_SLAVE_READ_PROCESSED,
ASPEED_I2C_SLAVE_WRITE_REQUESTED,
ASPEED_I2C_SLAVE_WRITE_RECEIVED,
+ ASPEED_I2C_SLAVE_GCALL_START,
+ ASPEED_I2C_SLAVE_GCALL_REQUESTED,
ASPEED_I2C_SLAVE_STOP,
};
@@ -152,6 +206,7 @@ struct aspeed_i2c_bus {
u32 divisor);
unsigned long parent_clk_frequency;
u32 bus_frequency;
+ u32 hw_timeout_ms;
/* Transaction state. */
enum aspeed_i2c_master_state master_state;
struct i2c_msg *msgs;
@@ -164,12 +219,43 @@ struct aspeed_i2c_bus {
int master_xfer_result;
/* Multi-master */
bool multi_master;
+ /* Buffer mode */
+ void __iomem *buf_base;
+ u8 buf_offset;
+ u8 buf_page;
+ /* DMA mode */
+ struct dma_pool *dma_pool;
+ dma_addr_t dma_handle;
+ u8 *dma_buf;
+ size_t dma_len;
+ /* Buffer/DMA mode */
+ size_t buf_size;
#if IS_ENABLED(CONFIG_I2C_SLAVE)
struct i2c_client *slave;
enum aspeed_i2c_slave_state slave_state;
+ /* General call */
+ bool general_call;
#endif /* CONFIG_I2C_SLAVE */
};
+static bool dump_debug __read_mostly;
+static int dump_debug_bus_id __read_mostly;
+
+#define I2C_HEX_DUMP(bus, addr, flags, buf, len) \
+ do { \
+ if (dump_debug && (bus)->adap.nr == dump_debug_bus_id) { \
+ char dump_info[100] = {0,}; \
+ char task_info[TASK_COMM_LEN]; \
+ get_task_comm(task_info, current); \
+ snprintf(dump_info, sizeof(dump_info), \
+ "bus_id:%d, addr:0x%02x, flags:0x%02x, task:%s(%d): ", \
+ (bus)->adap.nr, addr, flags, task_info, \
+ task_pid_nr(current)); \
+ print_hex_dump(KERN_ERR, dump_info, DUMP_PREFIX_NONE, \
+ 16, 1, buf, len, true); \
+ } \
+ } while (0)
+
static int aspeed_i2c_reset(struct aspeed_i2c_bus *bus);
static int aspeed_i2c_recover_bus(struct aspeed_i2c_bus *bus)
@@ -241,6 +327,123 @@ reset_out:
}
#if IS_ENABLED(CONFIG_I2C_SLAVE)
+static int aspeed_i2c_check_slave_error(u32 irq_status)
+{
+ if (irq_status & ASPEED_I2CD_INTR_SLAVE_INACTIVE_TIMEOUT)
+ return -EIO;
+
+ return 0;
+}
+
+static inline void
+aspeed_i2c_slave_handle_rx_done(struct aspeed_i2c_bus *bus, u32 irq_status,
+ u8 *value)
+{
+ if (bus->dma_buf &&
+ bus->slave_state == ASPEED_I2C_SLAVE_WRITE_RECEIVED &&
+ !(irq_status & ASPEED_I2CD_INTR_NORMAL_STOP))
+ *value = bus->dma_buf[0];
+ else if (bus->buf_base &&
+ bus->slave_state == ASPEED_I2C_SLAVE_WRITE_RECEIVED &&
+ !(irq_status & ASPEED_I2CD_INTR_NORMAL_STOP))
+ *value = readb(bus->buf_base);
+ else
+ *value = readl(bus->base + ASPEED_I2C_BYTE_BUF_REG) >> 8;
+}
+
+static inline void
+aspeed_i2c_slave_handle_normal_stop(struct aspeed_i2c_bus *bus, u32 irq_status,
+ u8 *value)
+{
+ int i, len;
+
+ if (bus->slave_state == ASPEED_I2C_SLAVE_WRITE_RECEIVED &&
+ irq_status & ASPEED_I2CD_INTR_RX_DONE) {
+ if (bus->dma_buf) {
+ len = bus->buf_size -
+ FIELD_GET(ASPEED_I2CD_DMA_LEN_MASK,
+ readl(bus->base +
+ ASPEED_I2C_DMA_LEN_REG));
+ for (i = 0; i < len; i++) {
+ *value = bus->dma_buf[i];
+ i2c_slave_event(bus->slave,
+ I2C_SLAVE_WRITE_RECEIVED,
+ value);
+ }
+ } else if (bus->buf_base) {
+ len = FIELD_GET(ASPEED_I2CD_BUF_RX_COUNT_MASK,
+ readl(bus->base +
+ ASPEED_I2C_BUF_CTRL_REG));
+ for (i = 0; i < len; i++) {
+ *value = readb(bus->buf_base + i);
+ i2c_slave_event(bus->slave,
+ I2C_SLAVE_WRITE_RECEIVED,
+ value);
+ }
+ }
+ }
+}
+
+static inline void
+aspeed_i2c_slave_handle_write_requested(struct aspeed_i2c_bus *bus, u8 *value)
+{
+ if (bus->dma_buf) {
+ writel(bus->dma_handle & ASPEED_I2CD_DMA_ADDR_MASK,
+ bus->base + ASPEED_I2C_DMA_ADDR_REG);
+ writel(FIELD_PREP(ASPEED_I2CD_DMA_LEN_MASK, bus->buf_size),
+ bus->base + ASPEED_I2C_DMA_LEN_REG);
+ writel(ASPEED_I2CD_RX_DMA_ENABLE,
+ bus->base + ASPEED_I2C_CMD_REG);
+ } else if (bus->buf_base) {
+ writel(FIELD_PREP(ASPEED_I2CD_BUF_RX_SIZE_MASK,
+ bus->buf_size - 1) |
+ FIELD_PREP(ASPEED_I2CD_BUF_OFFSET_MASK,
+ bus->buf_offset),
+ bus->base + ASPEED_I2C_BUF_CTRL_REG);
+ writel(ASPEED_I2CD_RX_BUFF_ENABLE,
+ bus->base + ASPEED_I2C_CMD_REG);
+ }
+}
+
+static inline void
+aspeed_i2c_slave_handle_write_received(struct aspeed_i2c_bus *bus, u8 *value)
+{
+ int i, len;
+
+ if (bus->dma_buf) {
+ len = bus->buf_size -
+ FIELD_GET(ASPEED_I2CD_DMA_LEN_MASK,
+ readl(bus->base +
+ ASPEED_I2C_DMA_LEN_REG));
+ for (i = 1; i < len; i++) {
+ *value = bus->dma_buf[i];
+ i2c_slave_event(bus->slave, I2C_SLAVE_WRITE_RECEIVED,
+ value);
+ }
+ writel(bus->dma_handle & ASPEED_I2CD_DMA_ADDR_MASK,
+ bus->base + ASPEED_I2C_DMA_ADDR_REG);
+ writel(FIELD_PREP(ASPEED_I2CD_DMA_LEN_MASK, bus->buf_size),
+ bus->base + ASPEED_I2C_DMA_LEN_REG);
+ writel(ASPEED_I2CD_RX_DMA_ENABLE,
+ bus->base + ASPEED_I2C_CMD_REG);
+ } else if (bus->buf_base) {
+ len = FIELD_GET(ASPEED_I2CD_BUF_RX_COUNT_MASK,
+ readl(bus->base +
+ ASPEED_I2C_BUF_CTRL_REG));
+ for (i = 1; i < len; i++) {
+ *value = readb(bus->buf_base + i);
+ i2c_slave_event(bus->slave, I2C_SLAVE_WRITE_RECEIVED,
+ value);
+ }
+ writel(FIELD_PREP(ASPEED_I2CD_BUF_RX_SIZE_MASK,
+ bus->buf_size - 1) |
+ FIELD_PREP(ASPEED_I2CD_BUF_OFFSET_MASK, bus->buf_offset),
+ bus->base + ASPEED_I2C_BUF_CTRL_REG);
+ writel(ASPEED_I2CD_RX_BUFF_ENABLE,
+ bus->base + ASPEED_I2C_CMD_REG);
+ }
+}
+
static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
{
u32 command, irq_handled = 0;
@@ -250,6 +453,14 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
if (!slave)
return 0;
+ if (aspeed_i2c_check_slave_error(irq_status)) {
+ dev_dbg(bus->dev, "received slave error interrupt: 0x%08x\n",
+ irq_status);
+ irq_handled |= (irq_status & ASPEED_I2CD_INTR_SLAVE_ERRORS);
+ bus->slave_state = ASPEED_I2C_SLAVE_INACTIVE;
+ return irq_handled;
+ }
+
command = readl(bus->base + ASPEED_I2C_CMD_REG);
/* Slave was requested, restart state machine. */
@@ -258,6 +469,12 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
bus->slave_state = ASPEED_I2C_SLAVE_START;
}
+ /* General call was requested, restart state machine. */
+ if (irq_status & ASPEED_I2CD_INTR_GCALL_ADDR) {
+ irq_handled |= ASPEED_I2CD_INTR_GCALL_ADDR;
+ bus->slave_state = ASPEED_I2C_SLAVE_GCALL_START;
+ }
+
/* Slave is not currently active, irq was for someone else. */
if (bus->slave_state == ASPEED_I2C_SLAVE_INACTIVE)
return irq_handled;
@@ -265,9 +482,21 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
dev_dbg(bus->dev, "slave irq status 0x%08x, cmd 0x%08x\n",
irq_status, command);
+ /*
+ * If a peer master sends messages too quickly before it processes
+ * previous slave DMA data handling, this indicator will be set. It's
+ * just a indicator and driver can't recover this case so just ignore
+ * it.
+ */
+ if (unlikely(irq_status &
+ ASPEED_I2CD_INTR_SLAVE_ADDR_RECEIVED_PENDING)) {
+ dev_dbg(bus->dev, "A slave addr match interrupt is pending.\n");
+ irq_handled |= ASPEED_I2CD_INTR_SLAVE_ADDR_RECEIVED_PENDING;
+ }
+
/* Slave was sent something. */
if (irq_status & ASPEED_I2CD_INTR_RX_DONE) {
- value = readl(bus->base + ASPEED_I2C_BYTE_BUF_REG) >> 8;
+ aspeed_i2c_slave_handle_rx_done(bus, irq_status, &value);
/* Handle address frame. */
if (bus->slave_state == ASPEED_I2C_SLAVE_START) {
if (value & 0x1)
@@ -276,15 +505,32 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
else
bus->slave_state =
ASPEED_I2C_SLAVE_WRITE_REQUESTED;
+ } else if (bus->slave_state == ASPEED_I2C_SLAVE_GCALL_START) {
+ /*
+ * I2C spec defines the second byte meaning like below.
+ * 0x06 : Reset and write programmable part of slave
+ * address by hardware.
+ * 0x04 : Write programmable part of slave address by
+ * hardware.
+ * 0x00 : No allowed.
+ *
+ * But in OpenBMC, we are going to use this
+ * 'General call' feature for IPMB message broadcasting
+ * so it delivers all data as is without any specific
+ * handling of the second byte.
+ */
+ bus->slave_state = ASPEED_I2C_SLAVE_GCALL_REQUESTED;
}
irq_handled |= ASPEED_I2CD_INTR_RX_DONE;
}
/* Slave was asked to stop. */
if (irq_status & ASPEED_I2CD_INTR_NORMAL_STOP) {
+ aspeed_i2c_slave_handle_normal_stop(bus, irq_status, &value);
irq_handled |= ASPEED_I2CD_INTR_NORMAL_STOP;
bus->slave_state = ASPEED_I2C_SLAVE_STOP;
}
+
if (irq_status & ASPEED_I2CD_INTR_TX_NAK &&
bus->slave_state == ASPEED_I2C_SLAVE_READ_PROCESSED) {
irq_handled |= ASPEED_I2CD_INTR_TX_NAK;
@@ -314,15 +560,22 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
case ASPEED_I2C_SLAVE_WRITE_REQUESTED:
bus->slave_state = ASPEED_I2C_SLAVE_WRITE_RECEIVED;
i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value);
+ aspeed_i2c_slave_handle_write_requested(bus, &value);
break;
case ASPEED_I2C_SLAVE_WRITE_RECEIVED:
i2c_slave_event(slave, I2C_SLAVE_WRITE_RECEIVED, &value);
+ aspeed_i2c_slave_handle_write_received(bus, &value);
+ break;
+ case ASPEED_I2C_SLAVE_GCALL_REQUESTED:
+ bus->slave_state = ASPEED_I2C_SLAVE_WRITE_RECEIVED;
+ i2c_slave_event(slave, I2C_SLAVE_GCALL_REQUESTED, &value);
break;
case ASPEED_I2C_SLAVE_STOP:
i2c_slave_event(slave, I2C_SLAVE_STOP, &value);
bus->slave_state = ASPEED_I2C_SLAVE_INACTIVE;
break;
case ASPEED_I2C_SLAVE_START:
+ case ASPEED_I2C_SLAVE_GCALL_START:
/* Slave was just started. Waiting for the next event. */;
break;
default:
@@ -336,12 +589,95 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
}
#endif /* CONFIG_I2C_SLAVE */
+static inline u32
+aspeed_i2c_prepare_rx_buf(struct aspeed_i2c_bus *bus, struct i2c_msg *msg)
+{
+ u32 command = 0;
+ int len;
+
+ if (msg->len > bus->buf_size) {
+ len = bus->buf_size;
+ } else {
+ len = msg->len;
+ command |= ASPEED_I2CD_M_S_RX_CMD_LAST;
+ }
+
+ if (bus->dma_buf) {
+ command |= ASPEED_I2CD_RX_DMA_ENABLE;
+
+ writel(bus->dma_handle & ASPEED_I2CD_DMA_ADDR_MASK,
+ bus->base + ASPEED_I2C_DMA_ADDR_REG);
+ writel(FIELD_PREP(ASPEED_I2CD_DMA_LEN_MASK, len),
+ bus->base + ASPEED_I2C_DMA_LEN_REG);
+ bus->dma_len = len;
+ } else {
+ command |= ASPEED_I2CD_RX_BUFF_ENABLE;
+
+ writel(FIELD_PREP(ASPEED_I2CD_BUF_RX_SIZE_MASK, len - 1) |
+ FIELD_PREP(ASPEED_I2CD_BUF_OFFSET_MASK, bus->buf_offset),
+ bus->base + ASPEED_I2C_BUF_CTRL_REG);
+ }
+
+ return command;
+}
+
+static inline u32
+aspeed_i2c_prepare_tx_buf(struct aspeed_i2c_bus *bus, struct i2c_msg *msg)
+{
+ u8 slave_addr = i2c_8bit_addr_from_msg(msg);
+ u32 command = 0;
+ int len;
+
+ if (msg->len + 1 > bus->buf_size)
+ len = bus->buf_size;
+ else
+ len = msg->len + 1;
+
+ if (bus->dma_buf) {
+ command |= ASPEED_I2CD_TX_DMA_ENABLE;
+
+ bus->dma_buf[0] = slave_addr;
+ memcpy(bus->dma_buf + 1, msg->buf, len);
+
+ writel(bus->dma_handle & ASPEED_I2CD_DMA_ADDR_MASK,
+ bus->base + ASPEED_I2C_DMA_ADDR_REG);
+ writel(FIELD_PREP(ASPEED_I2CD_DMA_LEN_MASK, len),
+ bus->base + ASPEED_I2C_DMA_LEN_REG);
+ bus->dma_len = len;
+ } else {
+ u8 wbuf[4];
+ int i;
+
+ command |= ASPEED_I2CD_TX_BUFF_ENABLE;
+
+ /*
+ * Yeah, it looks bad but byte writing on remapped I2C SRAM
+ * causes corruption so use this way to make dword writings.
+ */
+ wbuf[0] = slave_addr;
+ for (i = 1; i < len; i++) {
+ wbuf[i % 4] = msg->buf[i - 1];
+ if (i % 4 == 3)
+ writel(*(u32 *)wbuf, bus->buf_base + i - 3);
+ }
+ if (--i % 4 != 3)
+ writel(*(u32 *)wbuf, bus->buf_base + i - (i % 4));
+
+ writel(FIELD_PREP(ASPEED_I2CD_BUF_TX_COUNT_MASK, len - 1) |
+ FIELD_PREP(ASPEED_I2CD_BUF_OFFSET_MASK, bus->buf_offset),
+ bus->base + ASPEED_I2C_BUF_CTRL_REG);
+ }
+
+ bus->buf_index = len - 1;
+
+ return command;
+}
+
/* precondition: bus.lock has been acquired. */
static void aspeed_i2c_do_start(struct aspeed_i2c_bus *bus)
{
u32 command = ASPEED_I2CD_M_START_CMD | ASPEED_I2CD_M_TX_CMD;
struct i2c_msg *msg = &bus->msgs[bus->msgs_index];
- u8 slave_addr = i2c_8bit_addr_from_msg(msg);
#if IS_ENABLED(CONFIG_I2C_SLAVE)
/*
@@ -360,12 +696,22 @@ static void aspeed_i2c_do_start(struct aspeed_i2c_bus *bus)
if (msg->flags & I2C_M_RD) {
command |= ASPEED_I2CD_M_RX_CMD;
- /* Need to let the hardware know to NACK after RX. */
- if (msg->len == 1 && !(msg->flags & I2C_M_RECV_LEN))
- command |= ASPEED_I2CD_M_S_RX_CMD_LAST;
+ if (!(msg->flags & I2C_M_RECV_LEN)) {
+ if (msg->len && (bus->dma_buf || bus->buf_base))
+ command |= aspeed_i2c_prepare_rx_buf(bus, msg);
+
+ /* Need to let the hardware know to NACK after RX. */
+ if (msg->len <= 1)
+ command |= ASPEED_I2CD_M_S_RX_CMD_LAST;
+ }
+ } else if (msg->len && (bus->dma_buf || bus->buf_base)) {
+ command |= aspeed_i2c_prepare_tx_buf(bus, msg);
}
- writel(slave_addr, bus->base + ASPEED_I2C_BYTE_BUF_REG);
+ if (!(command & (ASPEED_I2CD_TX_BUFF_ENABLE |
+ ASPEED_I2CD_TX_DMA_ENABLE)))
+ writel(i2c_8bit_addr_from_msg(msg),
+ bus->base + ASPEED_I2C_BYTE_BUF_REG);
writel(command, bus->base + ASPEED_I2C_CMD_REG);
}
@@ -387,7 +733,7 @@ static void aspeed_i2c_next_msg_or_stop(struct aspeed_i2c_bus *bus)
}
}
-static int aspeed_i2c_is_irq_error(u32 irq_status)
+static int aspeed_i2c_check_master_error(u32 irq_status)
{
if (irq_status & ASPEED_I2CD_INTR_ARBIT_LOSS)
return -EAGAIN;
@@ -400,6 +746,134 @@ static int aspeed_i2c_is_irq_error(u32 irq_status)
return 0;
}
+static inline u32
+aspeed_i2c_master_handle_tx_first(struct aspeed_i2c_bus *bus,
+ struct i2c_msg *msg)
+{
+ u32 command = 0;
+
+ if (bus->dma_buf || bus->buf_base) {
+ int len;
+
+ if (msg->len - bus->buf_index > bus->buf_size)
+ len = bus->buf_size;
+ else
+ len = msg->len - bus->buf_index;
+
+ if (bus->dma_buf) {
+ command |= ASPEED_I2CD_TX_DMA_ENABLE;
+
+ memcpy(bus->dma_buf, msg->buf + bus->buf_index, len);
+
+
+ writel(bus->dma_handle & ASPEED_I2CD_DMA_ADDR_MASK,
+ bus->base + ASPEED_I2C_DMA_ADDR_REG);
+ writel(FIELD_PREP(ASPEED_I2CD_DMA_LEN_MASK, len),
+ bus->base + ASPEED_I2C_DMA_LEN_REG);
+ bus->dma_len = len;
+ } else {
+ u8 wbuf[4];
+ int i;
+
+ command |= ASPEED_I2CD_TX_BUFF_ENABLE;
+
+ if (msg->len - bus->buf_index > bus->buf_size)
+ len = bus->buf_size;
+ else
+ len = msg->len - bus->buf_index;
+
+ for (i = 0; i < len; i++) {
+ wbuf[i % 4] = msg->buf[bus->buf_index + i];
+ if (i % 4 == 3)
+ writel(*(u32 *)wbuf,
+ bus->buf_base + i - 3);
+ }
+ if (--i % 4 != 3)
+ writel(*(u32 *)wbuf,
+ bus->buf_base + i - (i % 4));
+
+ writel(FIELD_PREP(ASPEED_I2CD_BUF_TX_COUNT_MASK,
+ len - 1) |
+ FIELD_PREP(ASPEED_I2CD_BUF_OFFSET_MASK,
+ bus->buf_offset),
+ bus->base + ASPEED_I2C_BUF_CTRL_REG);
+ }
+
+ bus->buf_index += len;
+ } else {
+ writel(msg->buf[bus->buf_index++],
+ bus->base + ASPEED_I2C_BYTE_BUF_REG);
+ }
+
+ return command;
+}
+
+static inline void
+aspeed_i2c_master_handle_rx(struct aspeed_i2c_bus *bus, struct i2c_msg *msg)
+{
+ u8 recv_byte;
+ int len;
+
+ if (bus->dma_buf) {
+ len = bus->dma_len -
+ FIELD_GET(ASPEED_I2CD_DMA_LEN_MASK,
+ readl(bus->base + ASPEED_I2C_DMA_LEN_REG));
+
+ memcpy(msg->buf + bus->buf_index, bus->dma_buf, len);
+ bus->buf_index += len;
+ } else if (bus->buf_base) {
+ len = FIELD_GET(ASPEED_I2CD_BUF_RX_COUNT_MASK,
+ readl(bus->base + ASPEED_I2C_BUF_CTRL_REG));
+ memcpy_fromio(msg->buf + bus->buf_index, bus->buf_base, len);
+ bus->buf_index += len;
+ } else {
+ recv_byte = readl(bus->base + ASPEED_I2C_BYTE_BUF_REG) >> 8;
+ msg->buf[bus->buf_index++] = recv_byte;
+ }
+}
+
+static inline u32
+aspeed_i2c_master_handle_rx_next(struct aspeed_i2c_bus *bus,
+ struct i2c_msg *msg)
+{
+ u32 command = 0;
+
+ if (bus->dma_buf || bus->buf_base) {
+ int len;
+
+ if (msg->len - bus->buf_index > bus->buf_size) {
+ len = bus->buf_size;
+ } else {
+ len = msg->len - bus->buf_index;
+ command |= ASPEED_I2CD_M_S_RX_CMD_LAST;
+ }
+
+ if (bus->dma_buf) {
+ command |= ASPEED_I2CD_RX_DMA_ENABLE;
+
+ writel(bus->dma_handle & ASPEED_I2CD_DMA_ADDR_MASK,
+ bus->base + ASPEED_I2C_DMA_ADDR_REG);
+ writel(FIELD_PREP(ASPEED_I2CD_DMA_LEN_MASK, len),
+ bus->base + ASPEED_I2C_DMA_LEN_REG);
+ bus->dma_len = len;
+ } else {
+ command |= ASPEED_I2CD_RX_BUFF_ENABLE;
+
+ writel(FIELD_PREP(ASPEED_I2CD_BUF_RX_SIZE_MASK,
+ len - 1) |
+ FIELD_PREP(ASPEED_I2CD_BUF_TX_COUNT_MASK, 0) |
+ FIELD_PREP(ASPEED_I2CD_BUF_OFFSET_MASK,
+ bus->buf_offset),
+ bus->base + ASPEED_I2C_BUF_CTRL_REG);
+ }
+ } else {
+ if (bus->buf_index + 1 == msg->len)
+ command |= ASPEED_I2CD_M_S_RX_CMD_LAST;
+ }
+
+ return command;
+}
+
static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
{
u32 irq_handled = 0, command = 0;
@@ -418,13 +892,19 @@ static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
* should clear the command queue effectively taking us back to the
* INACTIVE state.
*/
- ret = aspeed_i2c_is_irq_error(irq_status);
+ ret = aspeed_i2c_check_master_error(irq_status);
if (ret) {
- dev_dbg(bus->dev, "received error interrupt: 0x%08x\n",
+ dev_dbg(bus->dev, "received master error interrupt: 0x%08x\n",
irq_status);
irq_handled |= (irq_status & ASPEED_I2CD_INTR_MASTER_ERRORS);
if (bus->master_state != ASPEED_I2C_MASTER_INACTIVE) {
bus->cmd_err = ret;
+ if (bus->master_state == ASPEED_I2C_MASTER_STOP)
+ irq_handled |= (irq_status &
+ ASPEED_I2CD_INTR_NORMAL_STOP);
+ if (ret == -EAGAIN)
+ irq_handled |= (irq_status &
+ ASPEED_I2CD_INTR_TX_ACK);
bus->master_state = ASPEED_I2C_MASTER_INACTIVE;
goto out_complete;
}
@@ -508,11 +988,10 @@ static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
fallthrough;
case ASPEED_I2C_MASTER_TX_FIRST:
if (bus->buf_index < msg->len) {
+ command = ASPEED_I2CD_M_TX_CMD;
+ command |= aspeed_i2c_master_handle_tx_first(bus, msg);
+ writel(command, bus->base + ASPEED_I2C_CMD_REG);
bus->master_state = ASPEED_I2C_MASTER_TX;
- writel(msg->buf[bus->buf_index++],
- bus->base + ASPEED_I2C_BYTE_BUF_REG);
- writel(ASPEED_I2CD_M_TX_CMD,
- bus->base + ASPEED_I2C_CMD_REG);
} else {
aspeed_i2c_next_msg_or_stop(bus);
}
@@ -529,26 +1008,26 @@ static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
}
irq_handled |= ASPEED_I2CD_INTR_RX_DONE;
- recv_byte = readl(bus->base + ASPEED_I2C_BYTE_BUF_REG) >> 8;
- msg->buf[bus->buf_index++] = recv_byte;
-
if (msg->flags & I2C_M_RECV_LEN) {
+ recv_byte = readl(bus->base +
+ ASPEED_I2C_BYTE_BUF_REG) >> 8;
if (unlikely(recv_byte > I2C_SMBUS_BLOCK_MAX)) {
bus->cmd_err = -EPROTO;
aspeed_i2c_do_stop(bus);
goto out_no_complete;
}
- msg->len = recv_byte +
- ((msg->flags & I2C_CLIENT_PEC) ? 2 : 1);
+ msg->len = recv_byte + ((msg->flags & I2C_CLIENT_PEC) ?
+ 2 : 1);
msg->flags &= ~I2C_M_RECV_LEN;
+ } else if (msg->len) {
+ aspeed_i2c_master_handle_rx(bus, msg);
}
if (bus->buf_index < msg->len) {
- bus->master_state = ASPEED_I2C_MASTER_RX;
command = ASPEED_I2CD_M_RX_CMD;
- if (bus->buf_index + 1 == msg->len)
- command |= ASPEED_I2CD_M_S_RX_CMD_LAST;
+ command |= aspeed_i2c_master_handle_rx_next(bus, msg);
writel(command, bus->base + ASPEED_I2C_CMD_REG);
+ bus->master_state = ASPEED_I2C_MASTER_RX;
} else {
aspeed_i2c_next_msg_or_stop(bus);
}
@@ -625,9 +1104,14 @@ static irqreturn_t aspeed_i2c_bus_irq(int irq, void *dev_id)
} else {
irq_handled = aspeed_i2c_slave_irq(bus, irq_remaining);
irq_remaining &= ~irq_handled;
- if (irq_remaining)
+ if (irq_remaining) {
irq_handled |= aspeed_i2c_master_irq(bus,
irq_remaining);
+ if (bus->master_state == ASPEED_I2C_MASTER_INACTIVE &&
+ bus->slave_state == ASPEED_I2C_SLAVE_INACTIVE)
+ irq_handled |= (irq_remaining &
+ ASPEED_I2CD_INTR_NORMAL_STOP);
+ }
}
/*
@@ -662,6 +1146,7 @@ static int aspeed_i2c_master_xfer(struct i2c_adapter *adap,
{
struct aspeed_i2c_bus *bus = i2c_get_adapdata(adap);
unsigned long time_left, flags;
+ int i;
spin_lock_irqsave(&bus->lock, flags);
bus->cmd_err = 0;
@@ -713,6 +1198,11 @@ static int aspeed_i2c_master_xfer(struct i2c_adapter *adap,
return -ETIMEDOUT;
}
+ for (i = 0; i < num; i++) {
+ I2C_HEX_DUMP(bus, msgs[i].addr, msgs[i].flags,
+ msgs[i].buf, msgs[i].len);
+ }
+
return bus->master_xfer_result;
}
@@ -736,6 +1226,8 @@ static void __aspeed_i2c_reg_slave(struct aspeed_i2c_bus *bus, u16 slave_addr)
/* Turn on slave mode. */
func_ctrl_reg_val = readl(bus->base + ASPEED_I2C_FUN_CTRL_REG);
func_ctrl_reg_val |= ASPEED_I2CD_SLAVE_EN;
+ if (bus->general_call)
+ func_ctrl_reg_val |= ASPEED_I2CD_GCALL_EN;
writel(func_ctrl_reg_val, bus->base + ASPEED_I2C_FUN_CTRL_REG);
}
@@ -774,6 +1266,8 @@ static int aspeed_i2c_unreg_slave(struct i2c_client *client)
/* Turn off slave mode. */
func_ctrl_reg_val = readl(bus->base + ASPEED_I2C_FUN_CTRL_REG);
func_ctrl_reg_val &= ~ASPEED_I2CD_SLAVE_EN;
+ if (bus->general_call)
+ func_ctrl_reg_val &= ~ASPEED_I2CD_GCALL_EN;
writel(func_ctrl_reg_val, bus->base + ASPEED_I2C_FUN_CTRL_REG);
bus->slave = NULL;
@@ -880,6 +1374,7 @@ static u32 aspeed_i2c_25xx_get_clk_reg_val(struct device *dev, u32 divisor)
/* precondition: bus.lock has been acquired. */
static int aspeed_i2c_init_clk(struct aspeed_i2c_bus *bus)
{
+ u32 timeout_base_divisor, timeout_tick_us, timeout_cycles;
u32 divisor, clk_reg_val;
divisor = DIV_ROUND_UP(bus->parent_clk_frequency, bus->bus_frequency);
@@ -888,8 +1383,46 @@ static int aspeed_i2c_init_clk(struct aspeed_i2c_bus *bus)
ASPEED_I2CD_TIME_THDSTA_MASK |
ASPEED_I2CD_TIME_TACST_MASK);
clk_reg_val |= bus->get_clk_reg_val(bus->dev, divisor);
+
+ if (bus->hw_timeout_ms) {
+ u8 div_max = ASPEED_I2CD_TIME_TIMEOUT_BASE_DIVISOR_MASK >>
+ ASPEED_I2CD_TIME_TIMEOUT_BASE_DIVISOR_SHIFT;
+ u8 cycles_max = ASPEED_I2CD_TIMEOUT_CYCLES_MASK >>
+ ASPEED_I2CD_TIMEOUT_CYCLES_SHIFT;
+
+ timeout_base_divisor = 0;
+
+ do {
+ timeout_tick_us = 1000 * (16384 <<
+ (timeout_base_divisor << 1)) /
+ (bus->parent_clk_frequency / 1000);
+
+ if (timeout_base_divisor == div_max ||
+ timeout_tick_us * ASPEED_I2CD_TIMEOUT_CYCLES_MASK >=
+ bus->hw_timeout_ms * 1000)
+ break;
+ } while (timeout_base_divisor++ < div_max);
+
+ if (timeout_tick_us) {
+ timeout_cycles = DIV_ROUND_UP(bus->hw_timeout_ms * 1000,
+ timeout_tick_us);
+ if (timeout_cycles == 0)
+ timeout_cycles = 1;
+ else if (timeout_cycles > cycles_max)
+ timeout_cycles = cycles_max;
+ } else {
+ timeout_cycles = 0;
+ }
+ } else {
+ timeout_base_divisor = 0;
+ timeout_cycles = 0;
+ }
+
+ clk_reg_val |= FIELD_PREP(ASPEED_I2CD_TIME_TIMEOUT_BASE_DIVISOR_MASK,
+ timeout_base_divisor);
+
writel(clk_reg_val, bus->base + ASPEED_I2C_AC_TIMING_REG1);
- writel(ASPEED_NO_TIMEOUT_CTRL, bus->base + ASPEED_I2C_AC_TIMING_REG2);
+ writel(timeout_cycles, bus->base + ASPEED_I2C_AC_TIMING_REG2);
return 0;
}
@@ -904,10 +1437,18 @@ static int aspeed_i2c_init(struct aspeed_i2c_bus *bus,
/* Disable everything. */
writel(0, bus->base + ASPEED_I2C_FUN_CTRL_REG);
+ device_property_read_u32(&pdev->dev, "aspeed,hw-timeout-ms",
+ &bus->hw_timeout_ms);
+ if (bus->hw_timeout_ms)
+ fun_ctrl_reg |= ASPEED_I2CD_BUS_AUTO_RECOVERY_EN;
+
ret = aspeed_i2c_init_clk(bus);
if (ret < 0)
return ret;
+ fun_ctrl_reg |= FIELD_PREP(ASPEED_I2CD_BUFFER_PAGE_SEL_MASK,
+ bus->buf_page);
+
if (of_property_read_bool(pdev->dev.of_node, "multi-master"))
bus->multi_master = true;
else
@@ -918,6 +1459,9 @@ static int aspeed_i2c_init(struct aspeed_i2c_bus *bus,
bus->base + ASPEED_I2C_FUN_CTRL_REG);
#if IS_ENABLED(CONFIG_I2C_SLAVE)
+ if (of_property_read_bool(pdev->dev.of_node, "general-call"))
+ bus->general_call = true;
+
/* If slave has already been registered, re-enable it. */
if (bus->slave)
__aspeed_i2c_reg_slave(bus, bus->slave->addr);
@@ -948,6 +1492,96 @@ static int aspeed_i2c_reset(struct aspeed_i2c_bus *bus)
return ret;
}
+static void aspeed_i2c_set_xfer_mode(struct aspeed_i2c_bus *bus)
+{
+ struct platform_device *pdev = to_platform_device(bus->dev);
+ bool sram_enabled = true;
+ int ret;
+
+ /*
+ * Enable I2C SRAM in case of AST2500.
+ * SRAM is enabled by default in AST2400 and AST2600.
+ */
+ if (of_device_is_compatible(pdev->dev.of_node,
+ "aspeed,ast2500-i2c-bus")) {
+ struct regmap *gr_regmap = syscon_regmap_lookup_by_compatible("aspeed,ast2500-i2c-gr");
+
+ if (IS_ERR(gr_regmap))
+ ret = PTR_ERR(gr_regmap);
+ else
+ ret = regmap_update_bits(gr_regmap,
+ ASPEED_I2CG_GLOBAL_CTRL_REG,
+ ASPEED_I2CG_SRAM_BUFFER_EN,
+ ASPEED_I2CG_SRAM_BUFFER_EN);
+
+ if (ret)
+ sram_enabled = false;
+ }
+
+ /*
+ * Only AST2500 and AST2600 support DMA mode under some limitations:
+ * I2C is sharing the DMA H/W with UHCI host controller and MCTP
+ * controller. Since those controllers operate with DMA mode only, I2C
+ * has to use buffer mode or byte mode instead if one of those
+ * controllers is enabled. Also make sure that if SD/eMMC or Port80
+ * snoop uses DMA mode instead of PIO or FIFO respectively, I2C can't
+ * use DMA mode.
+ */
+ if (sram_enabled && !IS_ENABLED(CONFIG_USB_UHCI_ASPEED) &&
+ !of_device_is_compatible(pdev->dev.of_node,
+ "aspeed,ast2400-i2c-bus")) {
+ u32 dma_len_max = ASPEED_I2CD_DMA_LEN_MASK >>
+ ASPEED_I2CD_DMA_LEN_SHIFT;
+
+ ret = device_property_read_u32(&pdev->dev,
+ "aspeed,dma-buf-size",
+ &bus->buf_size);
+ if (!ret && bus->buf_size > dma_len_max)
+ bus->buf_size = dma_len_max;
+ }
+
+ if (bus->buf_size) {
+ if (dma_set_mask(&pdev->dev, DMA_BIT_MASK(32))) {
+ dev_warn(&pdev->dev, "No suitable DMA available\n");
+ } else {
+ bus->dma_pool = dma_pool_create("i2c-aspeed",
+ &pdev->dev,
+ bus->buf_size,
+ ASPEED_I2CD_DMA_ALIGN,
+ 0);
+ if (bus->dma_pool)
+ bus->dma_buf = dma_pool_alloc(bus->dma_pool,
+ GFP_KERNEL,
+ &bus->dma_handle);
+
+ if (!bus->dma_buf) {
+ dev_warn(&pdev->dev,
+ "Cannot allocate DMA buffer\n");
+ dma_pool_destroy(bus->dma_pool);
+ }
+ }
+ }
+
+ if (!bus->dma_buf && sram_enabled) {
+ struct resource *res = platform_get_resource(pdev,
+ IORESOURCE_MEM, 1);
+
+ if (res && resource_size(res) >= 2)
+ bus->buf_base = devm_ioremap_resource(&pdev->dev, res);
+
+ if (!IS_ERR_OR_NULL(bus->buf_base)) {
+ bus->buf_size = resource_size(res);
+ if (of_device_is_compatible(pdev->dev.of_node,
+ "aspeed,ast2400-i2c-bus")) {
+ bus->buf_page = ((res->start >> 8) &
+ GENMASK(3, 0)) - 8;
+ bus->buf_offset = (res->start >> 2) &
+ ASPEED_I2CD_BUF_OFFSET_MASK;
+ }
+ }
+ }
+}
+
static const struct of_device_id aspeed_i2c_bus_of_table[] = {
{
.compatible = "aspeed,ast2400-i2c-bus",
@@ -970,18 +1604,26 @@ static int aspeed_i2c_probe_bus(struct platform_device *pdev)
const struct of_device_id *match;
struct aspeed_i2c_bus *bus;
struct clk *parent_clk;
- struct resource *res;
int irq, ret;
bus = devm_kzalloc(&pdev->dev, sizeof(*bus), GFP_KERNEL);
if (!bus)
return -ENOMEM;
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- bus->base = devm_ioremap_resource(&pdev->dev, res);
+ bus->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(bus->base))
return PTR_ERR(bus->base);
+ bus->dev = &pdev->dev;
+
+ /* Disable bus and clean up any left over interrupt state. */
+ writel(0, bus->base + ASPEED_I2C_FUN_CTRL_REG);
+ writel(0, bus->base + ASPEED_I2C_INTR_CTRL_REG);
+ writel(0xffffffff, bus->base + ASPEED_I2C_INTR_STS_REG);
+
+ /* Clear slave addresses. */
+ writel(0, bus->base + ASPEED_I2C_DEV_ADDR_REG);
+
parent_clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(parent_clk))
return PTR_ERR(parent_clk);
@@ -1012,46 +1654,47 @@ static int aspeed_i2c_probe_bus(struct platform_device *pdev)
bus->get_clk_reg_val = (u32 (*)(struct device *, u32))
match->data;
+ aspeed_i2c_set_xfer_mode(bus);
+
/* Initialize the I2C adapter */
spin_lock_init(&bus->lock);
init_completion(&bus->cmd_complete);
bus->adap.owner = THIS_MODULE;
- bus->adap.retries = 0;
bus->adap.algo = &aspeed_i2c_algo;
bus->adap.dev.parent = &pdev->dev;
bus->adap.dev.of_node = pdev->dev.of_node;
strlcpy(bus->adap.name, pdev->name, sizeof(bus->adap.name));
i2c_set_adapdata(&bus->adap, bus);
- bus->dev = &pdev->dev;
-
- /* Clean up any left over interrupt state. */
- writel(0, bus->base + ASPEED_I2C_INTR_CTRL_REG);
- writel(0xffffffff, bus->base + ASPEED_I2C_INTR_STS_REG);
- /*
- * bus.lock does not need to be held because the interrupt handler has
- * not been enabled yet.
- */
- ret = aspeed_i2c_init(bus, pdev);
- if (ret < 0)
- return ret;
-
irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
ret = devm_request_irq(&pdev->dev, irq, aspeed_i2c_bus_irq,
0, dev_name(&pdev->dev), bus);
if (ret < 0)
- return ret;
+ goto out_free_dma_buf;
+
+ ret = aspeed_i2c_init(bus, pdev);
+ if (ret < 0)
+ goto out_free_dma_buf;
ret = i2c_add_adapter(&bus->adap);
if (ret < 0)
- return ret;
+ goto out_free_dma_buf;
platform_set_drvdata(pdev, bus);
- dev_info(bus->dev, "i2c bus %d registered, irq %d\n",
- bus->adap.nr, irq);
+ dev_info(bus->dev, "i2c bus %d registered (%s mode), irq %d\n",
+ bus->adap.nr, bus->dma_buf ? "dma" :
+ bus->buf_base ? "buffer" : "byte",
+ irq);
return 0;
+
+out_free_dma_buf:
+ if (bus->dma_buf)
+ dma_pool_free(bus->dma_pool, bus->dma_buf, bus->dma_handle);
+ dma_pool_destroy(bus->dma_pool);
+
+ return ret;
}
static int aspeed_i2c_remove_bus(struct platform_device *pdev)
@@ -1069,6 +1712,10 @@ static int aspeed_i2c_remove_bus(struct platform_device *pdev)
reset_control_assert(bus->rst);
+ if (bus->dma_buf)
+ dma_pool_free(bus->dma_pool, bus->dma_buf, bus->dma_handle);
+ dma_pool_destroy(bus->dma_pool);
+
i2c_del_adapter(&bus->adap);
return 0;
@@ -1084,6 +1731,11 @@ static struct platform_driver aspeed_i2c_bus_driver = {
};
module_platform_driver(aspeed_i2c_bus_driver);
+module_param_named(dump_debug, dump_debug, bool, 0644);
+MODULE_PARM_DESC(dump_debug, "debug flag for dump printing");
+module_param_named(dump_debug_bus_id, dump_debug_bus_id, int, 0644);
+MODULE_PARM_DESC(dump_debug_bus_id, "bus id for dump debug printing");
+
MODULE_AUTHOR("Brendan Higgins <brendanhiggins@google.com>");
MODULE_DESCRIPTION("Aspeed I2C Bus Driver");
MODULE_LICENSE("GPL v2");
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index bdce6d3e5327..7d9c685af49c 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -1395,8 +1395,30 @@ int i2c_handle_smbus_host_notify(struct i2c_adapter *adap, unsigned short addr)
}
EXPORT_SYMBOL_GPL(i2c_handle_smbus_host_notify);
+static void i2c_adapter_hold(struct i2c_adapter *adapter, unsigned long timeout)
+{
+ mutex_lock(&adapter->hold_lock);
+ schedule_delayed_work(&adapter->unhold_work, timeout);
+}
+
+static void i2c_adapter_unhold(struct i2c_adapter *adapter)
+{
+ cancel_delayed_work_sync(&adapter->unhold_work);
+ mutex_unlock(&adapter->hold_lock);
+}
+
+static void i2c_adapter_unhold_work(struct work_struct *work)
+{
+ struct delayed_work *dwork = to_delayed_work(work);
+ struct i2c_adapter *adapter = container_of(dwork, struct i2c_adapter,
+ unhold_work);
+
+ mutex_unlock(&adapter->hold_lock);
+}
+
static int i2c_register_adapter(struct i2c_adapter *adap)
{
+ u32 bus_timeout_ms = 0;
int res = -EINVAL;
/* Can't register until after driver model init */
@@ -1424,8 +1446,15 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
INIT_LIST_HEAD(&adap->userspace_clients);
/* Set default timeout to 1 second if not already set */
- if (adap->timeout == 0)
- adap->timeout = HZ;
+ if (adap->timeout == 0) {
+ device_property_read_u32(&adap->dev, "bus-timeout-ms",
+ &bus_timeout_ms);
+ adap->timeout = bus_timeout_ms ?
+ msecs_to_jiffies(bus_timeout_ms) : HZ;
+ }
+
+ /* Set retries count if it has the property setting */
+ device_property_read_u32(&adap->dev, "#retries", &adap->retries);
/* register soft irqs for Host Notify */
res = i2c_setup_host_notify_irq_domain(adap);
@@ -1479,6 +1508,9 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter);
mutex_unlock(&core_lock);
+ mutex_init(&adap->hold_lock);
+ INIT_DELAYED_WORK(&adap->unhold_work, i2c_adapter_unhold_work);
+
return 0;
out_reg:
@@ -1699,6 +1731,8 @@ void i2c_del_adapter(struct i2c_adapter *adap)
idr_remove(&i2c_adapter_idr, adap->nr);
mutex_unlock(&core_lock);
+ i2c_adapter_unhold(adap);
+
/* Clear the device structure in case this adapter is ever going to be
added again */
memset(&adap->dev, 0, sizeof(adap->dev));
@@ -2017,7 +2051,9 @@ static int i2c_check_for_quirks(struct i2c_adapter *adap, struct i2c_msg *msgs,
*/
int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
{
+ enum i2c_hold_msg_type hold_msg = I2C_HOLD_MSG_NONE;
unsigned long orig_jiffies;
+ unsigned long timeout;
int ret, try;
if (WARN_ON(!msgs || num < 1))
@@ -2030,6 +2066,25 @@ int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
if (adap->quirks && i2c_check_for_quirks(adap, msgs, num))
return -EOPNOTSUPP;
+ /* Do not deliver a mux hold msg to root bus adapter */
+ if (!i2c_parent_is_i2c_adapter(adap)) {
+ hold_msg = i2c_check_hold_msg(msgs[num - 1].flags,
+ msgs[num - 1].len,
+ (u16 *)msgs[num - 1].buf);
+ if (hold_msg == I2C_HOLD_MSG_SET) {
+ timeout = msecs_to_jiffies(*(u16 *)msgs[num - 1].buf);
+ i2c_adapter_hold(adap, timeout);
+
+ if (--num == 0)
+ return 0;
+ } else if (hold_msg == I2C_HOLD_MSG_RESET) {
+ i2c_adapter_unhold(adap);
+ return 0;
+ } else if (hold_msg == I2C_HOLD_MSG_NONE) {
+ mutex_lock(&adap->hold_lock);
+ }
+ }
+
/*
* i2c_trace_msg_key gets enabled when tracepoint i2c_transfer gets
* enabled. This is an efficient way of keeping the for-loop from
@@ -2066,6 +2121,13 @@ int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
trace_i2c_result(adap, num, ret);
}
+ if (!i2c_parent_is_i2c_adapter(adap)) {
+ if (hold_msg == I2C_HOLD_MSG_SET && ret < 0)
+ i2c_adapter_unhold(adap);
+ else if (hold_msg == I2C_HOLD_MSG_NONE)
+ mutex_unlock(&adap->hold_lock);
+ }
+
return ret;
}
EXPORT_SYMBOL(__i2c_transfer);
@@ -2084,6 +2146,7 @@ EXPORT_SYMBOL(__i2c_transfer);
*/
int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
{
+ bool do_bus_lock = true;
int ret;
if (!adap->algo->master_xfer) {
@@ -2107,12 +2170,25 @@ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
* one (discarding status on the second message) or errno
* (discarding status on the first one).
*/
- ret = __i2c_lock_bus_helper(adap);
- if (ret)
- return ret;
+ /*
+ * Do not lock a bus for delivering an unhold msg to a mux
+ * adpater. This is just for a single length unhold msg case.
+ */
+ if (num == 1 && i2c_parent_is_i2c_adapter(adap) &&
+ i2c_check_hold_msg(msgs[0].flags, msgs[0].len,
+ (u16 *)msgs[0].buf) ==
+ I2C_HOLD_MSG_RESET)
+ do_bus_lock = false;
+
+ if (do_bus_lock) {
+ ret = __i2c_lock_bus_helper(adap);
+ if (ret)
+ return ret;
+ }
ret = __i2c_transfer(adap, msgs, num);
- i2c_unlock_bus(adap, I2C_LOCK_SEGMENT);
+ if (do_bus_lock)
+ i2c_unlock_bus(adap, I2C_LOCK_SEGMENT);
return ret;
}
diff --git a/drivers/i2c/i2c-core-smbus.c b/drivers/i2c/i2c-core-smbus.c
index f5c9787992e9..ea95d0482883 100644
--- a/drivers/i2c/i2c-core-smbus.c
+++ b/drivers/i2c/i2c-core-smbus.c
@@ -533,15 +533,29 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
unsigned short flags, char read_write,
u8 command, int protocol, union i2c_smbus_data *data)
{
+ bool do_bus_lock = true;
s32 res;
- res = __i2c_lock_bus_helper(adapter);
- if (res)
- return res;
+ /*
+ * Do not lock a bus for delivering an unhold msg to a mux adpater.
+ * This is just for a single length unhold msg case.
+ */
+ if (i2c_parent_is_i2c_adapter(adapter) &&
+ i2c_check_hold_msg(flags,
+ protocol == I2C_SMBUS_WORD_DATA ? 2 : 0,
+ &data->word) == I2C_HOLD_MSG_RESET)
+ do_bus_lock = false;
+
+ if (do_bus_lock) {
+ res = __i2c_lock_bus_helper(adapter);
+ if (res)
+ return res;
+ }
res = __i2c_smbus_xfer(adapter, addr, flags, read_write,
command, protocol, data);
- i2c_unlock_bus(adapter, I2C_LOCK_SEGMENT);
+ if (do_bus_lock)
+ i2c_unlock_bus(adapter, I2C_LOCK_SEGMENT);
return res;
}
diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c
index 774507b54b57..ce3c3ad3f129 100644
--- a/drivers/i2c/i2c-mux.c
+++ b/drivers/i2c/i2c-mux.c
@@ -36,21 +36,61 @@ struct i2c_mux_priv {
u32 chan_id;
};
+static void i2c_mux_hold(struct i2c_mux_core *muxc, unsigned long timeout)
+{
+ mutex_lock(&muxc->hold_lock);
+ schedule_delayed_work(&muxc->unhold_work, timeout);
+}
+
+static void i2c_mux_unhold(struct i2c_mux_core *muxc)
+{
+ cancel_delayed_work_sync(&muxc->unhold_work);
+ mutex_unlock(&muxc->hold_lock);
+}
+
+static void i2c_mux_unhold_work(struct work_struct *work)
+{
+ struct delayed_work *dwork = to_delayed_work(work);
+ struct i2c_mux_core *muxc = container_of(dwork, struct i2c_mux_core,
+ unhold_work);
+
+ mutex_unlock(&muxc->hold_lock);
+}
+
static int __i2c_mux_master_xfer(struct i2c_adapter *adap,
struct i2c_msg msgs[], int num)
{
struct i2c_mux_priv *priv = adap->algo_data;
struct i2c_mux_core *muxc = priv->muxc;
struct i2c_adapter *parent = muxc->parent;
+ enum i2c_hold_msg_type hold_msg;
+ unsigned long timeout;
int ret;
/* Switch to the right mux port and perform the transfer. */
+ hold_msg = i2c_check_hold_msg(msgs[num - 1].flags,
+ msgs[num - 1].len,
+ (u16 *)msgs[num - 1].buf);
+ if (hold_msg == I2C_HOLD_MSG_SET) {
+ timeout = msecs_to_jiffies(*(u16 *)msgs[num - 1].buf);
+ i2c_mux_hold(muxc, timeout);
+ } else if (hold_msg == I2C_HOLD_MSG_NONE) {
+ mutex_lock(&muxc->hold_lock);
+ }
ret = muxc->select(muxc, priv->chan_id);
if (ret >= 0)
ret = __i2c_transfer(parent, msgs, num);
- if (muxc->deselect)
- muxc->deselect(muxc, priv->chan_id);
+ if (hold_msg != I2C_HOLD_MSG_SET) {
+ if (muxc->deselect)
+ muxc->deselect(muxc, priv->chan_id);
+ if (hold_msg == I2C_HOLD_MSG_RESET)
+ i2c_mux_unhold(muxc);
+ else
+ mutex_unlock(&muxc->hold_lock);
+ } else if (hold_msg == I2C_HOLD_MSG_SET && ret < 0) {
+ i2c_mux_unhold(muxc);
+ }
return ret;
}
@@ -61,15 +101,32 @@ static int i2c_mux_master_xfer(struct i2c_adapter *adap,
struct i2c_mux_priv *priv = adap->algo_data;
struct i2c_mux_core *muxc = priv->muxc;
struct i2c_adapter *parent = muxc->parent;
+ enum i2c_hold_msg_type hold_msg;
+ unsigned long timeout;
int ret;
/* Switch to the right mux port and perform the transfer. */
+ hold_msg = i2c_check_hold_msg(msgs[num - 1].flags,
+ msgs[num - 1].len,
+ (u16 *)msgs[num - 1].buf);
+ if (hold_msg == I2C_HOLD_MSG_SET) {
+ timeout = msecs_to_jiffies(*(u16 *)msgs[num - 1].buf);
+ i2c_mux_hold(muxc, timeout);
+ } else if (hold_msg == I2C_HOLD_MSG_NONE) {
+ mutex_lock(&muxc->hold_lock);
+ }
ret = muxc->select(muxc, priv->chan_id);
if (ret >= 0)
ret = i2c_transfer(parent, msgs, num);
- if (muxc->deselect)
- muxc->deselect(muxc, priv->chan_id);
+ if (hold_msg != I2C_HOLD_MSG_SET) {
+ if (muxc->deselect)
+ muxc->deselect(muxc, priv->chan_id);
+ if (hold_msg == I2C_HOLD_MSG_RESET)
+ i2c_mux_unhold(muxc);
+ else
+ mutex_unlock(&muxc->hold_lock);
+ }
return ret;
}
@@ -82,16 +139,33 @@ static int __i2c_mux_smbus_xfer(struct i2c_adapter *adap,
struct i2c_mux_priv *priv = adap->algo_data;
struct i2c_mux_core *muxc = priv->muxc;
struct i2c_adapter *parent = muxc->parent;
+ enum i2c_hold_msg_type hold_msg;
+ unsigned long timeout;
int ret;
/* Select the right mux port and perform the transfer. */
+ hold_msg = i2c_check_hold_msg(flags,
+ size == I2C_SMBUS_WORD_DATA ? 2 : 0,
+ &data->word);
+ if (hold_msg == I2C_HOLD_MSG_SET) {
+ timeout = msecs_to_jiffies(data->word);
+ i2c_mux_hold(muxc, timeout);
+ } else if (hold_msg == I2C_HOLD_MSG_NONE) {
+ mutex_lock(&muxc->hold_lock);
+ }
ret = muxc->select(muxc, priv->chan_id);
if (ret >= 0)
ret = __i2c_smbus_xfer(parent, addr, flags,
read_write, command, size, data);
- if (muxc->deselect)
- muxc->deselect(muxc, priv->chan_id);
+ if (hold_msg != I2C_HOLD_MSG_SET) {
+ if (muxc->deselect)
+ muxc->deselect(muxc, priv->chan_id);
+ if (hold_msg == I2C_HOLD_MSG_RESET)
+ i2c_mux_unhold(muxc);
+ else
+ mutex_unlock(&muxc->hold_lock);
+ }
return ret;
}
@@ -104,16 +178,33 @@ static int i2c_mux_smbus_xfer(struct i2c_adapter *adap,
struct i2c_mux_priv *priv = adap->algo_data;
struct i2c_mux_core *muxc = priv->muxc;
struct i2c_adapter *parent = muxc->parent;
+ enum i2c_hold_msg_type hold_msg;
+ unsigned long timeout;
int ret;
/* Select the right mux port and perform the transfer. */
+ hold_msg = i2c_check_hold_msg(flags,
+ size == I2C_SMBUS_WORD_DATA ? 2 : 0,
+ &data->word);
+ if (hold_msg == I2C_HOLD_MSG_SET) {
+ timeout = msecs_to_jiffies(data->word);
+ i2c_mux_hold(muxc, timeout);
+ } else if (hold_msg == I2C_HOLD_MSG_NONE) {
+ mutex_lock(&muxc->hold_lock);
+ }
ret = muxc->select(muxc, priv->chan_id);
if (ret >= 0)
ret = i2c_smbus_xfer(parent, addr, flags,
read_write, command, size, data);
- if (muxc->deselect)
- muxc->deselect(muxc, priv->chan_id);
+ if (hold_msg != I2C_HOLD_MSG_SET) {
+ if (muxc->deselect)
+ muxc->deselect(muxc, priv->chan_id);
+ if (hold_msg == I2C_HOLD_MSG_RESET)
+ i2c_mux_unhold(muxc);
+ else
+ mutex_unlock(&muxc->hold_lock);
+ }
return ret;
}
@@ -263,6 +354,9 @@ struct i2c_mux_core *i2c_mux_alloc(struct i2c_adapter *parent,
muxc->deselect = deselect;
muxc->max_adapters = max_adapters;
+ mutex_init(&muxc->hold_lock);
+ INIT_DELAYED_WORK(&muxc->unhold_work, i2c_mux_unhold_work);
+
return muxc;
}
EXPORT_SYMBOL_GPL(i2c_mux_alloc);
@@ -441,6 +535,8 @@ void i2c_mux_del_adapters(struct i2c_mux_core *muxc)
{
char symlink_name[20];
+ i2c_mux_unhold(muxc);
+
while (muxc->num_adapters) {
struct i2c_adapter *adap = muxc->adapter[--muxc->num_adapters];
struct i2c_mux_priv *priv = adap->algo_data;
diff --git a/drivers/i2c/i2c-slave-mqueue.c b/drivers/i2c/i2c-slave-mqueue.c
new file mode 100644
index 000000000000..1d4db584b393
--- /dev/null
+++ b/drivers/i2c/i2c-slave-mqueue.c
@@ -0,0 +1,243 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2017 - 2018, Intel Corporation.
+
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/sysfs.h>
+
+#define MQ_MSGBUF_SIZE CONFIG_I2C_SLAVE_MQUEUE_MESSAGE_SIZE
+#define MQ_QUEUE_SIZE CONFIG_I2C_SLAVE_MQUEUE_QUEUE_SIZE
+#define MQ_QUEUE_NEXT(x) (((x) + 1) & (MQ_QUEUE_SIZE - 1))
+
+struct mq_msg {
+ int len;
+ u8 *buf;
+};
+
+struct mq_queue {
+ struct bin_attribute bin;
+ struct kernfs_node *kn;
+ struct i2c_client *client;
+
+ spinlock_t lock; /* spinlock for queue index handling */
+ int in;
+ int out;
+
+ struct mq_msg *curr;
+ int truncated; /* drop current if truncated */
+ struct mq_msg *queue;
+};
+
+static bool dump_debug __read_mostly;
+static int dump_debug_bus_id __read_mostly;
+
+#define I2C_HEX_DUMP(client, buf, len) \
+ do { \
+ if (dump_debug && \
+ (client)->adapter->nr == dump_debug_bus_id) { \
+ char dump_info[100] = {0,}; \
+ snprintf(dump_info, sizeof(dump_info), \
+ "bus_id:%d: ", (client)->adapter->nr); \
+ print_hex_dump(KERN_ERR, dump_info, DUMP_PREFIX_NONE, \
+ 16, 1, buf, len, true); \
+ } \
+ } while (0)
+
+static int i2c_slave_mqueue_callback(struct i2c_client *client,
+ enum i2c_slave_event event, u8 *val)
+{
+ struct mq_queue *mq = i2c_get_clientdata(client);
+ struct mq_msg *msg = mq->curr;
+ int ret = 0;
+
+ switch (event) {
+ case I2C_SLAVE_WRITE_REQUESTED:
+ case I2C_SLAVE_GCALL_REQUESTED:
+ mq->truncated = 0;
+
+ msg->len = 1;
+ msg->buf[0] = event == I2C_SLAVE_GCALL_REQUESTED ?
+ 0 : client->addr << 1;
+ break;
+
+ case I2C_SLAVE_WRITE_RECEIVED:
+ if (msg->len < MQ_MSGBUF_SIZE) {
+ msg->buf[msg->len++] = *val;
+ } else {
+ dev_err(&client->dev, "message is truncated!\n");
+ mq->truncated = 1;
+ ret = -EINVAL;
+ }
+ break;
+
+ case I2C_SLAVE_STOP:
+ if (unlikely(mq->truncated || msg->len < 2))
+ break;
+
+ spin_lock(&mq->lock);
+ mq->in = MQ_QUEUE_NEXT(mq->in);
+ mq->curr = &mq->queue[mq->in];
+ mq->curr->len = 0;
+
+ /* Flush the oldest message */
+ if (mq->out == mq->in)
+ mq->out = MQ_QUEUE_NEXT(mq->out);
+ spin_unlock(&mq->lock);
+
+ kernfs_notify(mq->kn);
+ break;
+
+ default:
+ *val = 0xFF;
+ break;
+ }
+
+ return ret;
+}
+
+static ssize_t i2c_slave_mqueue_bin_read(struct file *filp,
+ struct kobject *kobj,
+ struct bin_attribute *attr,
+ char *buf, loff_t pos, size_t count)
+{
+ struct mq_queue *mq;
+ struct mq_msg *msg;
+ unsigned long flags;
+ bool more = false;
+ ssize_t ret = 0;
+
+ mq = dev_get_drvdata(container_of(kobj, struct device, kobj));
+
+ spin_lock_irqsave(&mq->lock, flags);
+ if (mq->out != mq->in) {
+ msg = &mq->queue[mq->out];
+
+ if (msg->len <= count) {
+ ret = msg->len;
+ memcpy(buf, msg->buf, ret);
+ I2C_HEX_DUMP(mq->client, buf, ret);
+ } else {
+ ret = -EOVERFLOW; /* Drop this HUGE one. */
+ }
+
+ mq->out = MQ_QUEUE_NEXT(mq->out);
+ if (mq->out != mq->in)
+ more = true;
+ }
+ spin_unlock_irqrestore(&mq->lock, flags);
+
+ if (more)
+ kernfs_notify(mq->kn);
+
+ return ret;
+}
+
+static int i2c_slave_mqueue_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct device *dev = &client->dev;
+ struct mq_queue *mq;
+ int ret, i;
+ void *buf;
+
+ mq = devm_kzalloc(dev, sizeof(*mq), GFP_KERNEL);
+ if (!mq)
+ return -ENOMEM;
+
+ BUILD_BUG_ON(!is_power_of_2(MQ_QUEUE_SIZE));
+
+ mq->client = client;
+
+ buf = devm_kmalloc_array(dev, MQ_QUEUE_SIZE, MQ_MSGBUF_SIZE,
+ GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ mq->queue = devm_kzalloc(dev, sizeof(*mq->queue) * MQ_QUEUE_SIZE,
+ GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ for (i = 0; i < MQ_QUEUE_SIZE; i++)
+ mq->queue[i].buf = buf + i * MQ_MSGBUF_SIZE;
+
+ i2c_set_clientdata(client, mq);
+
+ spin_lock_init(&mq->lock);
+ mq->curr = &mq->queue[0];
+
+ sysfs_bin_attr_init(&mq->bin);
+ mq->bin.attr.name = "slave-mqueue";
+ mq->bin.attr.mode = 0400;
+ mq->bin.read = i2c_slave_mqueue_bin_read;
+ mq->bin.size = MQ_MSGBUF_SIZE * MQ_QUEUE_SIZE;
+
+ ret = sysfs_create_bin_file(&dev->kobj, &mq->bin);
+ if (ret)
+ return ret;
+
+ mq->kn = kernfs_find_and_get(dev->kobj.sd, mq->bin.attr.name);
+ if (!mq->kn) {
+ sysfs_remove_bin_file(&dev->kobj, &mq->bin);
+ return -EFAULT;
+ }
+
+ ret = i2c_slave_register(client, i2c_slave_mqueue_callback);
+ if (ret) {
+ kernfs_put(mq->kn);
+ sysfs_remove_bin_file(&dev->kobj, &mq->bin);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int i2c_slave_mqueue_remove(struct i2c_client *client)
+{
+ struct mq_queue *mq = i2c_get_clientdata(client);
+
+ i2c_slave_unregister(client);
+
+ kernfs_put(mq->kn);
+ sysfs_remove_bin_file(&client->dev.kobj, &mq->bin);
+
+ return 0;
+}
+
+static const struct i2c_device_id i2c_slave_mqueue_id[] = {
+ { "slave-mqueue", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, i2c_slave_mqueue_id);
+
+#if IS_ENABLED(CONFIG_OF)
+static const struct of_device_id i2c_slave_mqueue_of_match[] = {
+ { .compatible = "slave-mqueue", .data = (void *)0 },
+ { },
+};
+MODULE_DEVICE_TABLE(of, i2c_slave_mqueue_of_match);
+#endif
+
+static struct i2c_driver i2c_slave_mqueue_driver = {
+ .driver = {
+ .name = "i2c-slave-mqueue",
+ .of_match_table = of_match_ptr(i2c_slave_mqueue_of_match),
+ },
+ .probe = i2c_slave_mqueue_probe,
+ .remove = i2c_slave_mqueue_remove,
+ .id_table = i2c_slave_mqueue_id,
+};
+module_i2c_driver(i2c_slave_mqueue_driver);
+
+module_param_named(dump_debug, dump_debug, bool, 0644);
+MODULE_PARM_DESC(dump_debug, "debug flag for dump printing");
+module_param_named(dump_debug_bus_id, dump_debug_bus_id, int, 0644);
+MODULE_PARM_DESC(dump_debug_bus_id, "bus id for dump debug printing");
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Haiyue Wang <haiyue.wang@linux.intel.com>");
+MODULE_DESCRIPTION("I2C slave mode for receiving and queuing messages");