summaryrefslogtreecommitdiff
path: root/drivers/gpio/gpio-winbond.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/gpio/gpio-winbond.c')
-rw-r--r--drivers/gpio/gpio-winbond.c732
1 files changed, 732 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-winbond.c b/drivers/gpio/gpio-winbond.c
new file mode 100644
index 000000000000..7f8f5b02e31d
--- /dev/null
+++ b/drivers/gpio/gpio-winbond.c
@@ -0,0 +1,732 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * GPIO interface for Winbond Super I/O chips
+ * Currently, only W83627UHG (Nuvoton NCT6627UD) is supported.
+ *
+ * Author: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/gpio/driver.h>
+#include <linux/ioport.h>
+#include <linux/isa.h>
+#include <linux/module.h>
+
+#define WB_GPIO_DRIVER_NAME KBUILD_MODNAME
+
+#define WB_SIO_BASE 0x2e
+#define WB_SIO_BASE_HIGH 0x4e
+
+#define WB_SIO_EXT_ENTER_KEY 0x87
+#define WB_SIO_EXT_EXIT_KEY 0xaa
+
+/* global chip registers */
+
+#define WB_SIO_REG_LOGICAL 0x07
+
+#define WB_SIO_REG_CHIP_MSB 0x20
+#define WB_SIO_REG_CHIP_LSB 0x21
+
+#define WB_SIO_CHIP_ID_W83627UHG 0xa230
+#define WB_SIO_CHIP_ID_W83627UHG_MASK GENMASK(15, 4)
+
+#define WB_SIO_REG_DPD 0x22
+#define WB_SIO_REG_DPD_UARTA 4
+#define WB_SIO_REG_DPD_UARTB 5
+
+#define WB_SIO_REG_IDPD 0x23
+#define WB_SIO_REG_IDPD_UARTC 4
+#define WB_SIO_REG_IDPD_UARTD 5
+#define WB_SIO_REG_IDPD_UARTE 6
+#define WB_SIO_REG_IDPD_UARTF 7
+
+#define WB_SIO_REG_GLOBAL_OPT 0x24
+#define WB_SIO_REG_GO_ENFDC 1
+
+#define WB_SIO_REG_OVTGPIO3456 0x29
+#define WB_SIO_REG_OG3456_G3PP 3
+#define WB_SIO_REG_OG3456_G4PP 4
+#define WB_SIO_REG_OG3456_G5PP 5
+#define WB_SIO_REG_OG3456_G6PP 7
+
+#define WB_SIO_REG_I2C_PS 0x2a
+#define WB_SIO_REG_I2CPS_I2CFS 1
+
+#define WB_SIO_REG_GPIO1_MF 0x2c
+#define WB_SIO_REG_G1MF_G1PP 6
+#define WB_SIO_REG_G1MF_G2PP 7
+#define WB_SIO_REG_G1MF_FS_MASK GENMASK(1, 0)
+#define WB_SIO_REG_G1MF_FS_IR_OFF 0
+#define WB_SIO_REG_G1MF_FS_IR 1
+#define WB_SIO_REG_G1MF_FS_GPIO1 2
+#define WB_SIO_REG_G1MF_FS_UARTB 3
+
+/* not an actual device number, just a value meaning 'no device' */
+#define WB_SIO_DEV_NONE 0xff
+
+/* registers with offsets >= 0x30 are specific for a particular device */
+
+/* UART B logical device */
+#define WB_SIO_DEV_UARTB 0x03
+#define WB_SIO_UARTB_REG_ENABLE 0x30
+#define WB_SIO_UARTB_ENABLE_ON 0
+
+/* UART C logical device */
+#define WB_SIO_DEV_UARTC 0x06
+#define WB_SIO_UARTC_REG_ENABLE 0x30
+#define WB_SIO_UARTC_ENABLE_ON 0
+
+/* GPIO3, GPIO4 logical device */
+#define WB_SIO_DEV_GPIO34 0x07
+#define WB_SIO_GPIO34_REG_ENABLE 0x30
+#define WB_SIO_GPIO34_ENABLE_3 0
+#define WB_SIO_GPIO34_ENABLE_4 1
+#define WB_SIO_GPIO34_REG_IO3 0xe0
+#define WB_SIO_GPIO34_REG_DATA3 0xe1
+#define WB_SIO_GPIO34_REG_INV3 0xe2
+#define WB_SIO_GPIO34_REG_IO4 0xe4
+#define WB_SIO_GPIO34_REG_DATA4 0xe5
+#define WB_SIO_GPIO34_REG_INV4 0xe6
+
+/* WDTO, PLED, GPIO5, GPIO6 logical device */
+#define WB_SIO_DEV_WDGPIO56 0x08
+#define WB_SIO_WDGPIO56_REG_ENABLE 0x30
+#define WB_SIO_WDGPIO56_ENABLE_5 1
+#define WB_SIO_WDGPIO56_ENABLE_6 2
+#define WB_SIO_WDGPIO56_REG_IO5 0xe0
+#define WB_SIO_WDGPIO56_REG_DATA5 0xe1
+#define WB_SIO_WDGPIO56_REG_INV5 0xe2
+#define WB_SIO_WDGPIO56_REG_IO6 0xe4
+#define WB_SIO_WDGPIO56_REG_DATA6 0xe5
+#define WB_SIO_WDGPIO56_REG_INV6 0xe6
+
+/* GPIO1, GPIO2, SUSLED logical device */
+#define WB_SIO_DEV_GPIO12 0x09
+#define WB_SIO_GPIO12_REG_ENABLE 0x30
+#define WB_SIO_GPIO12_ENABLE_1 0
+#define WB_SIO_GPIO12_ENABLE_2 1
+#define WB_SIO_GPIO12_REG_IO1 0xe0
+#define WB_SIO_GPIO12_REG_DATA1 0xe1
+#define WB_SIO_GPIO12_REG_INV1 0xe2
+#define WB_SIO_GPIO12_REG_IO2 0xe4
+#define WB_SIO_GPIO12_REG_DATA2 0xe5
+#define WB_SIO_GPIO12_REG_INV2 0xe6
+
+/* UART D logical device */
+#define WB_SIO_DEV_UARTD 0x0d
+#define WB_SIO_UARTD_REG_ENABLE 0x30
+#define WB_SIO_UARTD_ENABLE_ON 0
+
+/* UART E logical device */
+#define WB_SIO_DEV_UARTE 0x0e
+#define WB_SIO_UARTE_REG_ENABLE 0x30
+#define WB_SIO_UARTE_ENABLE_ON 0
+
+/*
+ * for a description what a particular field of this struct means please see
+ * a description of the relevant module parameter at the bottom of this file
+ */
+struct winbond_gpio_params {
+ unsigned long base;
+ unsigned long gpios;
+ unsigned long ppgpios;
+ unsigned long odgpios;
+ bool pledgpio;
+ bool beepgpio;
+ bool i2cgpio;
+};
+
+static struct winbond_gpio_params params;
+
+static int winbond_sio_enter(unsigned long base)
+{
+ if (!request_muxed_region(base, 2, WB_GPIO_DRIVER_NAME))
+ return -EBUSY;
+
+ /*
+ * datasheet says two successive writes of the "key" value are needed
+ * in order for chip to enter the "Extended Function Mode"
+ */
+ outb(WB_SIO_EXT_ENTER_KEY, base);
+ outb(WB_SIO_EXT_ENTER_KEY, base);
+
+ return 0;
+}
+
+static void winbond_sio_select_logical(unsigned long base, u8 dev)
+{
+ outb(WB_SIO_REG_LOGICAL, base);
+ outb(dev, base + 1);
+}
+
+static void winbond_sio_leave(unsigned long base)
+{
+ outb(WB_SIO_EXT_EXIT_KEY, base);
+
+ release_region(base, 2);
+}
+
+static void winbond_sio_reg_write(unsigned long base, u8 reg, u8 data)
+{
+ outb(reg, base);
+ outb(data, base + 1);
+}
+
+static u8 winbond_sio_reg_read(unsigned long base, u8 reg)
+{
+ outb(reg, base);
+ return inb(base + 1);
+}
+
+static void winbond_sio_reg_bset(unsigned long base, u8 reg, u8 bit)
+{
+ u8 val;
+
+ val = winbond_sio_reg_read(base, reg);
+ val |= BIT(bit);
+ winbond_sio_reg_write(base, reg, val);
+}
+
+static void winbond_sio_reg_bclear(unsigned long base, u8 reg, u8 bit)
+{
+ u8 val;
+
+ val = winbond_sio_reg_read(base, reg);
+ val &= ~BIT(bit);
+ winbond_sio_reg_write(base, reg, val);
+}
+
+static bool winbond_sio_reg_btest(unsigned long base, u8 reg, u8 bit)
+{
+ return winbond_sio_reg_read(base, reg) & BIT(bit);
+}
+
+/**
+ * struct winbond_gpio_port_conflict - possibly conflicting device information
+ * @name: device name (NULL means no conflicting device defined)
+ * @dev: Super I/O logical device number where the testreg register
+ * is located (or WB_SIO_DEV_NONE - don't select any
+ * logical device)
+ * @testreg: register number where the testbit bit is located
+ * @testbit: index of a bit to check whether an actual conflict exists
+ * @warnonly: if set then a conflict isn't fatal (just warn about it),
+ * otherwise disable the particular GPIO port if a conflict
+ * is detected
+ */
+struct winbond_gpio_port_conflict {
+ const char *name;
+ u8 dev;
+ u8 testreg;
+ u8 testbit;
+ bool warnonly;
+};
+
+/**
+ * struct winbond_gpio_info - information about a particular GPIO port (device)
+ * @dev: Super I/O logical device number of the registers
+ * specified below
+ * @enablereg: port enable bit register number
+ * @enablebit: index of a port enable bit
+ * @outputreg: output driver mode bit register number
+ * @outputppbit: index of a push-pull output driver mode bit
+ * @ioreg: data direction register number
+ * @invreg: pin data inversion register number
+ * @datareg: pin data register number
+ * @conflict: description of a device that possibly conflicts with
+ * this port
+ */
+struct winbond_gpio_info {
+ u8 dev;
+ u8 enablereg;
+ u8 enablebit;
+ u8 outputreg;
+ u8 outputppbit;
+ u8 ioreg;
+ u8 invreg;
+ u8 datareg;
+ struct winbond_gpio_port_conflict conflict;
+};
+
+static const struct winbond_gpio_info winbond_gpio_infos[6] = {
+ { /* 0 */
+ .dev = WB_SIO_DEV_GPIO12,
+ .enablereg = WB_SIO_GPIO12_REG_ENABLE,
+ .enablebit = WB_SIO_GPIO12_ENABLE_1,
+ .outputreg = WB_SIO_REG_GPIO1_MF,
+ .outputppbit = WB_SIO_REG_G1MF_G1PP,
+ .ioreg = WB_SIO_GPIO12_REG_IO1,
+ .invreg = WB_SIO_GPIO12_REG_INV1,
+ .datareg = WB_SIO_GPIO12_REG_DATA1,
+ .conflict = {
+ .name = "UARTB",
+ .dev = WB_SIO_DEV_UARTB,
+ .testreg = WB_SIO_UARTB_REG_ENABLE,
+ .testbit = WB_SIO_UARTB_ENABLE_ON,
+ .warnonly = true
+ }
+ },
+ { /* 1 */
+ .dev = WB_SIO_DEV_GPIO12,
+ .enablereg = WB_SIO_GPIO12_REG_ENABLE,
+ .enablebit = WB_SIO_GPIO12_ENABLE_2,
+ .outputreg = WB_SIO_REG_GPIO1_MF,
+ .outputppbit = WB_SIO_REG_G1MF_G2PP,
+ .ioreg = WB_SIO_GPIO12_REG_IO2,
+ .invreg = WB_SIO_GPIO12_REG_INV2,
+ .datareg = WB_SIO_GPIO12_REG_DATA2
+ /* special conflict handling so doesn't use conflict data */
+ },
+ { /* 2 */
+ .dev = WB_SIO_DEV_GPIO34,
+ .enablereg = WB_SIO_GPIO34_REG_ENABLE,
+ .enablebit = WB_SIO_GPIO34_ENABLE_3,
+ .outputreg = WB_SIO_REG_OVTGPIO3456,
+ .outputppbit = WB_SIO_REG_OG3456_G3PP,
+ .ioreg = WB_SIO_GPIO34_REG_IO3,
+ .invreg = WB_SIO_GPIO34_REG_INV3,
+ .datareg = WB_SIO_GPIO34_REG_DATA3,
+ .conflict = {
+ .name = "UARTC",
+ .dev = WB_SIO_DEV_UARTC,
+ .testreg = WB_SIO_UARTC_REG_ENABLE,
+ .testbit = WB_SIO_UARTC_ENABLE_ON,
+ .warnonly = true
+ }
+ },
+ { /* 3 */
+ .dev = WB_SIO_DEV_GPIO34,
+ .enablereg = WB_SIO_GPIO34_REG_ENABLE,
+ .enablebit = WB_SIO_GPIO34_ENABLE_4,
+ .outputreg = WB_SIO_REG_OVTGPIO3456,
+ .outputppbit = WB_SIO_REG_OG3456_G4PP,
+ .ioreg = WB_SIO_GPIO34_REG_IO4,
+ .invreg = WB_SIO_GPIO34_REG_INV4,
+ .datareg = WB_SIO_GPIO34_REG_DATA4,
+ .conflict = {
+ .name = "UARTD",
+ .dev = WB_SIO_DEV_UARTD,
+ .testreg = WB_SIO_UARTD_REG_ENABLE,
+ .testbit = WB_SIO_UARTD_ENABLE_ON,
+ .warnonly = true
+ }
+ },
+ { /* 4 */
+ .dev = WB_SIO_DEV_WDGPIO56,
+ .enablereg = WB_SIO_WDGPIO56_REG_ENABLE,
+ .enablebit = WB_SIO_WDGPIO56_ENABLE_5,
+ .outputreg = WB_SIO_REG_OVTGPIO3456,
+ .outputppbit = WB_SIO_REG_OG3456_G5PP,
+ .ioreg = WB_SIO_WDGPIO56_REG_IO5,
+ .invreg = WB_SIO_WDGPIO56_REG_INV5,
+ .datareg = WB_SIO_WDGPIO56_REG_DATA5,
+ .conflict = {
+ .name = "UARTE",
+ .dev = WB_SIO_DEV_UARTE,
+ .testreg = WB_SIO_UARTE_REG_ENABLE,
+ .testbit = WB_SIO_UARTE_ENABLE_ON,
+ .warnonly = true
+ }
+ },
+ { /* 5 */
+ .dev = WB_SIO_DEV_WDGPIO56,
+ .enablereg = WB_SIO_WDGPIO56_REG_ENABLE,
+ .enablebit = WB_SIO_WDGPIO56_ENABLE_6,
+ .outputreg = WB_SIO_REG_OVTGPIO3456,
+ .outputppbit = WB_SIO_REG_OG3456_G6PP,
+ .ioreg = WB_SIO_WDGPIO56_REG_IO6,
+ .invreg = WB_SIO_WDGPIO56_REG_INV6,
+ .datareg = WB_SIO_WDGPIO56_REG_DATA6,
+ .conflict = {
+ .name = "FDC",
+ .dev = WB_SIO_DEV_NONE,
+ .testreg = WB_SIO_REG_GLOBAL_OPT,
+ .testbit = WB_SIO_REG_GO_ENFDC,
+ .warnonly = false
+ }
+ }
+};
+
+/* returns whether changing a pin is allowed */
+static bool winbond_gpio_get_info(unsigned int *gpio_num,
+ const struct winbond_gpio_info **info)
+{
+ bool allow_changing = true;
+ unsigned long i;
+
+ for_each_set_bit(i, &params.gpios, BITS_PER_LONG) {
+ if (*gpio_num < 8)
+ break;
+
+ *gpio_num -= 8;
+ }
+
+ *info = &winbond_gpio_infos[i];
+
+ /*
+ * GPIO2 (the second port) shares some pins with a basic PC
+ * functionality, which is very likely controlled by the firmware.
+ * Don't allow changing these pins by default.
+ */
+ if (i == 1) {
+ if (*gpio_num == 0 && !params.pledgpio)
+ allow_changing = false;
+ else if (*gpio_num == 1 && !params.beepgpio)
+ allow_changing = false;
+ else if ((*gpio_num == 5 || *gpio_num == 6) && !params.i2cgpio)
+ allow_changing = false;
+ }
+
+ return allow_changing;
+}
+
+static int winbond_gpio_get(struct gpio_chip *gc, unsigned int offset)
+{
+ unsigned long *base = gpiochip_get_data(gc);
+ const struct winbond_gpio_info *info;
+ bool val;
+
+ winbond_gpio_get_info(&offset, &info);
+
+ val = winbond_sio_enter(*base);
+ if (val)
+ return val;
+
+ winbond_sio_select_logical(*base, info->dev);
+
+ val = winbond_sio_reg_btest(*base, info->datareg, offset);
+ if (winbond_sio_reg_btest(*base, info->invreg, offset))
+ val = !val;
+
+ winbond_sio_leave(*base);
+
+ return val;
+}
+
+static int winbond_gpio_direction_in(struct gpio_chip *gc, unsigned int offset)
+{
+ unsigned long *base = gpiochip_get_data(gc);
+ const struct winbond_gpio_info *info;
+ int ret;
+
+ if (!winbond_gpio_get_info(&offset, &info))
+ return -EACCES;
+
+ ret = winbond_sio_enter(*base);
+ if (ret)
+ return ret;
+
+ winbond_sio_select_logical(*base, info->dev);
+
+ winbond_sio_reg_bset(*base, info->ioreg, offset);
+
+ winbond_sio_leave(*base);
+
+ return 0;
+}
+
+static int winbond_gpio_direction_out(struct gpio_chip *gc,
+ unsigned int offset,
+ int val)
+{
+ unsigned long *base = gpiochip_get_data(gc);
+ const struct winbond_gpio_info *info;
+ int ret;
+
+ if (!winbond_gpio_get_info(&offset, &info))
+ return -EACCES;
+
+ ret = winbond_sio_enter(*base);
+ if (ret)
+ return ret;
+
+ winbond_sio_select_logical(*base, info->dev);
+
+ winbond_sio_reg_bclear(*base, info->ioreg, offset);
+
+ if (winbond_sio_reg_btest(*base, info->invreg, offset))
+ val = !val;
+
+ if (val)
+ winbond_sio_reg_bset(*base, info->datareg, offset);
+ else
+ winbond_sio_reg_bclear(*base, info->datareg, offset);
+
+ winbond_sio_leave(*base);
+
+ return 0;
+}
+
+static void winbond_gpio_set(struct gpio_chip *gc, unsigned int offset,
+ int val)
+{
+ unsigned long *base = gpiochip_get_data(gc);
+ const struct winbond_gpio_info *info;
+
+ if (!winbond_gpio_get_info(&offset, &info))
+ return;
+
+ if (winbond_sio_enter(*base) != 0)
+ return;
+
+ winbond_sio_select_logical(*base, info->dev);
+
+ if (winbond_sio_reg_btest(*base, info->invreg, offset))
+ val = !val;
+
+ if (val)
+ winbond_sio_reg_bset(*base, info->datareg, offset);
+ else
+ winbond_sio_reg_bclear(*base, info->datareg, offset);
+
+ winbond_sio_leave(*base);
+}
+
+static struct gpio_chip winbond_gpio_chip = {
+ .base = -1,
+ .label = WB_GPIO_DRIVER_NAME,
+ .owner = THIS_MODULE,
+ .can_sleep = true,
+ .get = winbond_gpio_get,
+ .direction_input = winbond_gpio_direction_in,
+ .set = winbond_gpio_set,
+ .direction_output = winbond_gpio_direction_out,
+};
+
+static void winbond_gpio_configure_port0_pins(unsigned long base)
+{
+ unsigned int val;
+
+ val = winbond_sio_reg_read(base, WB_SIO_REG_GPIO1_MF);
+ if ((val & WB_SIO_REG_G1MF_FS_MASK) == WB_SIO_REG_G1MF_FS_GPIO1)
+ return;
+
+ pr_warn("GPIO1 pins were connected to something else (%.2x), fixing\n",
+ val);
+
+ val &= ~WB_SIO_REG_G1MF_FS_MASK;
+ val |= WB_SIO_REG_G1MF_FS_GPIO1;
+
+ winbond_sio_reg_write(base, WB_SIO_REG_GPIO1_MF, val);
+}
+
+static void winbond_gpio_configure_port1_check_i2c(unsigned long base)
+{
+ params.i2cgpio = !winbond_sio_reg_btest(base, WB_SIO_REG_I2C_PS,
+ WB_SIO_REG_I2CPS_I2CFS);
+ if (!params.i2cgpio)
+ pr_warn("disabling GPIO2.5 and GPIO2.6 as I2C is enabled\n");
+}
+
+static bool winbond_gpio_configure_port(unsigned long base, unsigned int idx)
+{
+ const struct winbond_gpio_info *info = &winbond_gpio_infos[idx];
+ const struct winbond_gpio_port_conflict *conflict = &info->conflict;
+
+ /* is there a possible conflicting device defined? */
+ if (conflict->name != NULL) {
+ if (conflict->dev != WB_SIO_DEV_NONE)
+ winbond_sio_select_logical(base, conflict->dev);
+
+ if (winbond_sio_reg_btest(base, conflict->testreg,
+ conflict->testbit)) {
+ if (conflict->warnonly)
+ pr_warn("enabled GPIO%u share pins with active %s\n",
+ idx + 1, conflict->name);
+ else {
+ pr_warn("disabling GPIO%u as %s is enabled\n",
+ idx + 1, conflict->name);
+ return false;
+ }
+ }
+ }
+
+ /* GPIO1 and GPIO2 need some (additional) special handling */
+ if (idx == 0)
+ winbond_gpio_configure_port0_pins(base);
+ else if (idx == 1)
+ winbond_gpio_configure_port1_check_i2c(base);
+
+ winbond_sio_select_logical(base, info->dev);
+
+ winbond_sio_reg_bset(base, info->enablereg, info->enablebit);
+
+ if (params.ppgpios & BIT(idx))
+ winbond_sio_reg_bset(base, info->outputreg,
+ info->outputppbit);
+ else if (params.odgpios & BIT(idx))
+ winbond_sio_reg_bclear(base, info->outputreg,
+ info->outputppbit);
+ else
+ pr_notice("GPIO%u pins are %s\n", idx + 1,
+ winbond_sio_reg_btest(base, info->outputreg,
+ info->outputppbit) ?
+ "push-pull" :
+ "open drain");
+
+ return true;
+}
+
+static int winbond_gpio_configure(unsigned long base)
+{
+ unsigned long i;
+
+ for_each_set_bit(i, &params.gpios, BITS_PER_LONG)
+ if (!winbond_gpio_configure_port(base, i))
+ __clear_bit(i, &params.gpios);
+
+ if (!params.gpios) {
+ pr_err("please use 'gpios' module parameter to select some active GPIO ports to enable\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int winbond_gpio_check_chip(unsigned long base)
+{
+ int ret;
+ unsigned int chip;
+
+ ret = winbond_sio_enter(base);
+ if (ret)
+ return ret;
+
+ chip = winbond_sio_reg_read(base, WB_SIO_REG_CHIP_MSB) << 8;
+ chip |= winbond_sio_reg_read(base, WB_SIO_REG_CHIP_LSB);
+
+ pr_notice("chip ID at %lx is %.4x\n", base, chip);
+
+ if ((chip & WB_SIO_CHIP_ID_W83627UHG_MASK) !=
+ WB_SIO_CHIP_ID_W83627UHG) {
+ pr_err("not an our chip\n");
+ ret = -ENODEV;
+ }
+
+ winbond_sio_leave(base);
+
+ return ret;
+}
+
+static int winbond_gpio_imatch(struct device *dev, unsigned int id)
+{
+ unsigned long gpios_rem;
+ int ret;
+
+ gpios_rem = params.gpios & ~GENMASK(ARRAY_SIZE(winbond_gpio_infos) - 1,
+ 0);
+ if (gpios_rem) {
+ pr_warn("unknown ports (%lx) enabled in GPIO ports bitmask\n",
+ gpios_rem);
+ params.gpios &= ~gpios_rem;
+ }
+
+ if (params.ppgpios & params.odgpios) {
+ pr_err("some GPIO ports are set both to push-pull and open drain mode at the same time\n");
+ return 0;
+ }
+
+ if (params.base != 0)
+ return winbond_gpio_check_chip(params.base) == 0;
+
+ /*
+ * if the 'base' module parameter is unset probe two chip default
+ * I/O port bases
+ */
+ params.base = WB_SIO_BASE;
+ ret = winbond_gpio_check_chip(params.base);
+ if (ret == 0)
+ return 1;
+ if (ret != -ENODEV && ret != -EBUSY)
+ return 0;
+
+ params.base = WB_SIO_BASE_HIGH;
+ return winbond_gpio_check_chip(params.base) == 0;
+}
+
+static int winbond_gpio_iprobe(struct device *dev, unsigned int id)
+{
+ int ret;
+
+ if (params.base == 0)
+ return -EINVAL;
+
+ ret = winbond_sio_enter(params.base);
+ if (ret)
+ return ret;
+
+ ret = winbond_gpio_configure(params.base);
+
+ winbond_sio_leave(params.base);
+
+ if (ret)
+ return ret;
+
+ /*
+ * Add 8 gpios for every GPIO port that was enabled in gpios
+ * module parameter (that wasn't disabled earlier in
+ * winbond_gpio_configure() & co. due to, for example, a pin conflict).
+ */
+ winbond_gpio_chip.ngpio = hweight_long(params.gpios) * 8;
+
+ /*
+ * GPIO6 port has only 5 pins, so if it is enabled we have to adjust
+ * the total count appropriately
+ */
+ if (params.gpios & BIT(5))
+ winbond_gpio_chip.ngpio -= (8 - 5);
+
+ winbond_gpio_chip.parent = dev;
+
+ return devm_gpiochip_add_data(dev, &winbond_gpio_chip, &params.base);
+}
+
+static struct isa_driver winbond_gpio_idriver = {
+ .driver = {
+ .name = WB_GPIO_DRIVER_NAME,
+ },
+ .match = winbond_gpio_imatch,
+ .probe = winbond_gpio_iprobe,
+};
+
+module_isa_driver(winbond_gpio_idriver, 1);
+
+module_param_named(base, params.base, ulong, 0444);
+MODULE_PARM_DESC(base,
+ "I/O port base (when unset - probe chip default ones)");
+
+/* This parameter sets which GPIO devices (ports) we enable */
+module_param_named(gpios, params.gpios, ulong, 0444);
+MODULE_PARM_DESC(gpios,
+ "bitmask of GPIO ports to enable (bit 0 - GPIO1, bit 1 - GPIO2, etc.");
+
+/*
+ * These two parameters below set how we configure GPIO ports output drivers.
+ * It can't be a one bitmask since we need three values per port: push-pull,
+ * open-drain and keep as-is (this is the default).
+ */
+module_param_named(ppgpios, params.ppgpios, ulong, 0444);
+MODULE_PARM_DESC(ppgpios,
+ "bitmask of GPIO ports to set to push-pull mode (bit 0 - GPIO1, bit 1 - GPIO2, etc.");
+
+module_param_named(odgpios, params.odgpios, ulong, 0444);
+MODULE_PARM_DESC(odgpios,
+ "bitmask of GPIO ports to set to open drain mode (bit 0 - GPIO1, bit 1 - GPIO2, etc.");
+
+/*
+ * GPIO2.0 and GPIO2.1 control a basic PC functionality that we
+ * don't allow tinkering with by default (it is very likely that the
+ * firmware owns these pins).
+ * These two parameters below allow overriding these prohibitions.
+ */
+module_param_named(pledgpio, params.pledgpio, bool, 0644);
+MODULE_PARM_DESC(pledgpio,
+ "enable changing value of GPIO2.0 bit (Power LED), default no.");
+
+module_param_named(beepgpio, params.beepgpio, bool, 0644);
+MODULE_PARM_DESC(beepgpio,
+ "enable changing value of GPIO2.1 bit (BEEP), default no.");
+
+MODULE_AUTHOR("Maciej S. Szmigiero <mail@maciej.szmigiero.name>");
+MODULE_DESCRIPTION("GPIO interface for Winbond Super I/O chips");
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-11 23:57:05 +0300