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-rw-r--r--drivers/i2c/busses/Kconfig3
-rw-r--r--drivers/i2c/busses/i2c-designware-core.h3
-rw-r--r--drivers/i2c/busses/i2c-designware-platdrv.c78
3 files changed, 81 insertions, 3 deletions
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index c748beaaa890..14e2e93a5698 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -541,8 +541,9 @@ config I2C_DESIGNWARE_SLAVE
config I2C_DESIGNWARE_PLATFORM
tristate "Synopsys DesignWare Platform"
- select I2C_DESIGNWARE_CORE
depends on (ACPI && COMMON_CLK) || !ACPI
+ select I2C_DESIGNWARE_CORE
+ select MFD_SYSCON if MIPS_BAIKAL_T1
help
If you say yes to this option, support will be included for the
Synopsys DesignWare I2C adapter.
diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h
index f5bbe3d6bcf8..556673a1f61b 100644
--- a/drivers/i2c/busses/i2c-designware-core.h
+++ b/drivers/i2c/busses/i2c-designware-core.h
@@ -183,6 +183,7 @@ struct reset_control;
* struct dw_i2c_dev - private i2c-designware data
* @dev: driver model device node
* @map: IO registers map
+ * @sysmap: System controller registers map
* @base: IO registers pointer
* @ext: Extended IO registers pointer
* @cmd_complete: tx completion indicator
@@ -235,6 +236,7 @@ struct reset_control;
struct dw_i2c_dev {
struct device *dev;
struct regmap *map;
+ struct regmap *sysmap;
void __iomem *base;
void __iomem *ext;
struct completion cmd_complete;
@@ -290,6 +292,7 @@ struct dw_i2c_dev {
#define ACCESS_NO_IRQ_SUSPEND 0x00000002
#define MODEL_MSCC_OCELOT 0x00000100
+#define MODEL_BAIKAL_BT1 0x00000200
#define MODEL_MASK 0x00000f00
int i2c_dw_init_regmap(struct dw_i2c_dev *dev);
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 9d467fa0e163..b55c730f28cf 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -18,6 +18,7 @@
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_data/i2c-designware.h>
@@ -25,6 +26,7 @@
#include <linux/pm.h>
#include <linux/pm_runtime.h>
#include <linux/property.h>
+#include <linux/regmap.h>
#include <linux/reset.h>
#include <linux/sched.h>
#include <linux/slab.h>
@@ -58,6 +60,63 @@ MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
#endif
#ifdef CONFIG_OF
+#define BT1_I2C_CTL 0x100
+#define BT1_I2C_CTL_ADDR_MASK GENMASK(7, 0)
+#define BT1_I2C_CTL_WR BIT(8)
+#define BT1_I2C_CTL_GO BIT(31)
+#define BT1_I2C_DI 0x104
+#define BT1_I2C_DO 0x108
+
+static int bt1_i2c_read(void *context, unsigned int reg, unsigned int *val)
+{
+ struct dw_i2c_dev *dev = context;
+ int ret;
+
+ /*
+ * Note these methods shouldn't ever fail because the system controller
+ * registers are memory mapped. We check the return value just in case.
+ */
+ ret = regmap_write(dev->sysmap, BT1_I2C_CTL,
+ BT1_I2C_CTL_GO | (reg & BT1_I2C_CTL_ADDR_MASK));
+ if (ret)
+ return ret;
+
+ return regmap_read(dev->sysmap, BT1_I2C_DO, val);
+}
+
+static int bt1_i2c_write(void *context, unsigned int reg, unsigned int val)
+{
+ struct dw_i2c_dev *dev = context;
+ int ret;
+
+ ret = regmap_write(dev->sysmap, BT1_I2C_DI, val);
+ if (ret)
+ return ret;
+
+ return regmap_write(dev->sysmap, BT1_I2C_CTL,
+ BT1_I2C_CTL_GO | BT1_I2C_CTL_WR | (reg & BT1_I2C_CTL_ADDR_MASK));
+}
+
+static struct regmap_config bt1_i2c_cfg = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .fast_io = true,
+ .reg_read = bt1_i2c_read,
+ .reg_write = bt1_i2c_write,
+ .max_register = DW_IC_COMP_TYPE,
+};
+
+static int bt1_i2c_request_regs(struct dw_i2c_dev *dev)
+{
+ dev->sysmap = syscon_node_to_regmap(dev->dev->of_node->parent);
+ if (IS_ERR(dev->sysmap))
+ return PTR_ERR(dev->sysmap);
+
+ dev->map = devm_regmap_init(dev->dev, NULL, dev, &bt1_i2c_cfg);
+ return PTR_ERR_OR_ZERO(dev->map);
+}
+
#define MSCC_ICPU_CFG_TWI_DELAY 0x0
#define MSCC_ICPU_CFG_TWI_DELAY_ENABLE BIT(0)
#define MSCC_ICPU_CFG_TWI_SPIKE_FILTER 0x4
@@ -90,10 +149,16 @@ static int dw_i2c_of_configure(struct platform_device *pdev)
static const struct of_device_id dw_i2c_of_match[] = {
{ .compatible = "snps,designware-i2c", },
{ .compatible = "mscc,ocelot-i2c", .data = (void *)MODEL_MSCC_OCELOT },
+ { .compatible = "baikal,bt1-sys-i2c", .data = (void *)MODEL_BAIKAL_BT1 },
{},
};
MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
#else
+static int bt1_i2c_request_regs(struct dw_i2c_dev *dev)
+{
+ return -ENODEV;
+}
+
static inline int dw_i2c_of_configure(struct platform_device *pdev)
{
return -ENODEV;
@@ -111,10 +176,19 @@ static void dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *dev)
static int dw_i2c_plat_request_regs(struct dw_i2c_dev *dev)
{
struct platform_device *pdev = to_platform_device(dev->dev);
+ int ret;
- dev->base = devm_platform_ioremap_resource(pdev, 0);
+ switch (dev->flags & MODEL_MASK) {
+ case MODEL_BAIKAL_BT1:
+ ret = bt1_i2c_request_regs(dev);
+ break;
+ default:
+ dev->base = devm_platform_ioremap_resource(pdev, 0);
+ ret = PTR_ERR_OR_ZERO(dev->base);
+ break;
+ }
- return PTR_ERR_OR_ZERO(dev->base);
+ return ret;
}
static int dw_i2c_plat_probe(struct platform_device *pdev)