From: Oleksandr Suvorov oleksandr.suvorov@toradex.com

The FXL6408 GPIO expander manages critical devices, including on-module USB hub. Configure the expander to switch the USB hub into bypass mode, allowing to use on-carrier-board USB hub.

Signed-off-by: Oleksandr Suvorov oleksandr.suvorov@toradex.com Signed-off-by: Oleksandr Suvorov oleksandr.suvorov@foundries.io ---

Changes in v2: - Kconfig: add better description for the config option. - gpio-fxl6408.c: -- improve registers' naming. -- fix code style (comments, etc.). -- reimplement fxl6408_read() reducing number of parameters. -- change return value of fxl6408_is_output() to bool. -- replace IS_ERR_VALUE() macros with simple x < 0 where it's possible. -- fxl6408_set_direction(): fix type of parameter "dir". -- fix return error codes to avoid using the predefined in the driver model ones. -- removed extra debug code. -- expand TODO list.

arch/arm/dts/fsl-imx8qxp-colibri.dts | 27 +++++++++++++++++++++++++++ configs/colibri-imx8x_defconfig | 1 + 2 files changed, 28 insertions(+)

diff --git a/arch/arm/dts/fsl-imx8qxp-colibri.dts b/arch/arm/dts/fsl-imx8qxp-colibri.dts index 11ece34c02..df992ac639 100644 --- a/arch/arm/dts/fsl-imx8qxp-colibri.dts +++ b/arch/arm/dts/fsl-imx8qxp-colibri.dts @@ -129,6 +129,14 @@ >; };

+ /* On Module I2C */ + pinctrl_i2c0: i2c0grp { + fsl,pins = < + SC_P_MIPI_CSI0_GPIO0_00_ADMA_I2C0_SCL 0x06000021 + SC_P_MIPI_CSI0_GPIO0_01_ADMA_I2C0_SDA 0x06000021 + >; + }; + /* Off Module I2C */ pinctrl_i2c1: i2c1grp { fsl,pins = < @@ -298,6 +306,25 @@ }; };

+&i2c0 { + #address-cells = <1>; + #size-cells = <0>; + clock-frequency = <100000>; + pinctrl-names = "default"; + pinctrl-0 = <&pinctrl_i2c0>; + status = "okay"; + + /* GPIO expander */ + gpio_expander_43: gpio-expander@43 { + compatible = "fcs,fxl6408"; + gpio-controller; + #gpio-cells = <2>; + reg = <0x43>; + initial_io_dir = <0xff>; + initial_output = <0x05>; + }; +}; + &i2c1 { #address-cells = <1>; #size-cells = <0>; diff --git a/configs/colibri-imx8x_defconfig b/configs/colibri-imx8x_defconfig index a0816acc27..fbe6e575a3 100644 --- a/configs/colibri-imx8x_defconfig +++ b/configs/colibri-imx8x_defconfig @@ -38,6 +38,7 @@ CONFIG_TFTP_BLOCKSIZE=4096 CONFIG_TFTP_TSIZE=y CONFIG_CLK_IMX8=y CONFIG_CPU=y +CONFIG_FXL6408_GPIO=y CONFIG_MXC_GPIO=y CONFIG_DM_I2C=y CONFIG_SYS_I2C_IMX_LPI2C=y

Hi Marcel,

On Thu, Sep 9, 2021 at 4:29 PM Marcel Ziswiler marcel.ziswiler@toradex.com wrote:

Hi Oleksandr

Just one tiny nit-pick. Otherwise looks good and works great. Thanks!

Thanks, I thought I'd already fixed that warning :) Will be fixed in the next revision.

On Sat, 2021-08-28 at 13:23 +0300, Oleksandr Suvorov wrote:

...

From: Oleksandr Suvorov oleksandr.suvorov@toradex.com

Initial support for Fairchild's 8 bit I2C gpio expander FXL6408. The CONFIG_FXL6408_GPIO define enables support for such devices.

Based on: https://patchwork.kernel.org/patch/9148419/

Signed-off-by: Oleksandr Suvorov oleksandr.suvorov@toradex.com

Hehe.

Oh, thanks for pointing that out :) I've finished it being in Toradex, just forgot to resend a fixed version. :) But as now the patch is changed, probably it's better to refresh the field :)

...

Reviewed-by: Simon Glass sjg@chromium.org Signed-off-by: Oleksandr Suvorov oleksandr.suvorov@foundries.io

Tested-by: Marcel Ziswiler marcel.ziswiler@toradex.com

Thank you!

...

---

Changes in v2: None

drivers/gpio/Kconfig | 7 + drivers/gpio/Makefile | 1 + drivers/gpio/gpio-fxl6408.c | 366 ++++++++++++++++++++++++++++++++++++ 3 files changed, 374 insertions(+) create mode 100644 drivers/gpio/gpio-fxl6408.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index 4a89c1a62b..f56e4cc261 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -123,6 +123,13 @@ config DA8XX_GPIO help This driver supports the DA8xx GPIO controller

+config FXL6408_GPIO

•   bool "FXL6408 I2C GPIO expander driver"
  

•   depends on DM_GPIO && DM_I2C
  

•   help
  

•     This driver supports the Fairchild FXL6408 device. FXL6408 is a
  

•     fully configurable 8-bit I2C-controlled GPIO expander.
  

config INTEL_BROADWELL_GPIO bool "Intel Broadwell GPIO driver" depends on DM diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index 58f4704f6b..83d8b5c9d8 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -16,6 +16,7 @@ obj-$(CONFIG_AT91_GPIO) += at91_gpio.o obj-$(CONFIG_ATMEL_PIO4) += atmel_pio4.o obj-$(CONFIG_BCM6345_GPIO) += bcm6345_gpio.o obj-$(CONFIG_CORTINA_GPIO) += cortina_gpio.o +obj-$(CONFIG_FXL6408_GPIO) += gpio-fxl6408.o obj-$(CONFIG_INTEL_GPIO) += intel_gpio.o obj-$(CONFIG_INTEL_ICH6_GPIO) += intel_ich6_gpio.o obj-$(CONFIG_INTEL_BROADWELL_GPIO) += intel_broadwell_gpio.o diff --git a/drivers/gpio/gpio-fxl6408.c b/drivers/gpio/gpio-fxl6408.c new file mode 100644 index 0000000000..8a86f32365 --- /dev/null +++ b/drivers/gpio/gpio-fxl6408.c @@ -0,0 +1,366 @@ +// SPDX-License-Identifier: GPL-2.0 +/*

• • Copyright (C) 2021 Toradex
• • Copyright (C) 2016 Broadcom
• */

+/**

• • DOC: FXL6408 I2C to GPIO expander.
• • This chip has 8 GPIO lines out of it, and is controlled by an I2C
• • bus (a pair of lines), providing 4x expansion of GPIO lines. It
• • also provides an interrupt line out for notifying of state changes.
• • Any preconfigured state will be left in place until the GPIO lines
• • get activated. At power on, everything is treated as an input,
• • default input is HIGH and pulled-up, all interrupts are masked.
• • Documentation can be found at:
• • https://www.fairchildsemi.com/datasheets/FX/FXL6408.pdf
• • This driver bases on:
• • • the original driver by Eric Anholt eric@anholt.net:
• • https://patchwork.kernel.org/patch/9148419/
• • • the Toradex version by Max Krummenacher max.krummenacher@toradex.com:
• • http://git.toradex.com/cgit/linux-toradex.git/tree/drivers/gpio/gpio-fxl6408...
• • • the U-boot PCA953x driver by Peng Fan van.freenix@gmail.com:
• • drivers/gpio/pca953x_gpio.c
• • TODO:
• • • Add interrupts support
• • • Replace deprecated callbacks direction_input/output() with set_flags()
• */

+#include <common.h> +#include <dm.h> +#include <dm/device_compat.h> +#include <i2c.h> +#include <log.h> +#include <asm-generic/gpio.h> +#include <asm/global_data.h> +#include <linux/bitops.h> +#include <dt-bindings/gpio/gpio.h>

+#define REG_DEVID_CTRL 0x01 +# define SW_RST BIT(0) +# define RST_INT BIT(1) +/* 0b101 is the Manufacturer's ID assigned to Fairchild by Nokia */ +# define MF_ID_FAIRCHILD 5

+/* Bits set here indicate that the GPIO is an output */ +#define REG_IO_DIR 0x03

+/*

• • Bits set here, when the corresponding bit of REG_IO_DIR is set, drive
• • the output high instead of low.
• */

+#define REG_OUT_STATE 0x05

+/* Bits here make the output High-Z, instead of the OUTPUT value */ +#define REG_OUT_HIGH_Z 0x07

+/*

• • Bits here define the expected input state of the GPIO.
• • INTERRUPT_STATUS bits will be set when the INPUT transitions away
• • from this value.
• */

+#define REG_IN_DEFAULT_STATE 0x09

+/*

• • Bits here enable either pull up or pull down according to
• • REG_PULL_MODE.
• */

+#define REG_PULL_ENABLE 0x0b

+/*

• • Bits set here selects a pull-up/pull-down state of pin, which
• • is configured as Input and the corresponding REG_PULL_ENABLE bit is
• • set.
• */

+#define REG_PULL_MODE 0x0d

+/* Returns the current status (1 = HIGH) of the input pins */ +#define REG_IN_STATUS 0x0f

+/* Mask of pins which can generate interrupts */ +#define REG_INT_MASK 0x11

+/* Mask of pins which have generated an interrupt. Cleared on read */ +#define REG_INT_STATUS 0x13

+/* Manufacturer's ID getting from Device ID & Ctrl register */ +enum {

•   MF_ID_MASK = GENMASK(7, 5),
  

•   MF_ID_SHIFT = 5,
  

+};

+/* Firmware revision getting from Device ID & Ctrl register */ +enum {

•   FW_REV_MASK = GENMASK(4, 2),
  

•   FW_REV_SHIFT = 2,
  

+};

+enum io_direction {

•   DIR_IN,
  

•   DIR_OUT,
  

+};

+/*

• • struct fxl6408_info - Data for fxl6408
• • @dev: udevice structure for the device
• • @addr: i2c slave address
• • @reg_io_dir: hold the value of direction register
• • @reg_output: hold the value of output register
• */

+struct fxl6408_info {

•   struct udevice *dev;
  

•   int addr;
  

•   u8 device_id;
  

•   u8 reg_io_dir;
  

•   u8 reg_output;
  

+};

+static inline int fxl6408_write(struct udevice *dev, int reg, u8 val) +{

•   return dm_i2c_write(dev, reg, &val, 1);
  

+}

+static int fxl6408_read(struct udevice *dev, int reg) +{

•   int ret;
  

•   u8 tmp;
  

•   ret = dm_i2c_read(dev, reg, &tmp, 1);
  

•   if (!ret)
  

•           ret = tmp;
  

•   return ret;
  

+}

+/*

• • fxl6408_is_output() - check whether the gpio configures as either

• •                  output or input.
    

• • Return: false - input, true - output.
• */

+static bool fxl6408_is_output(struct udevice *dev, int offset) +{

•   struct fxl6408_info *info = dev_get_plat(dev);
  

•   return info->reg_io_dir & BIT(offset);
  

+}

+static int fxl6408_get_value(struct udevice *dev, uint offset) +{

•   int ret, reg = fxl6408_is_output(dev, offset) ? REG_OUT_STATE : REG_IN_STATUS;
  

•   ret = fxl6408_read(dev, reg);
  

•   if (ret < 0)
  

•           return ret;
  

•   return !!(ret & BIT(offset));
  

+}

+static int fxl6408_set_value(struct udevice *dev, uint offset, int value) +{

•   struct fxl6408_info *info = dev_get_plat(dev);
  

•   u8 val;
  

•   int ret;
  

•   if (value)
  

•           val = info->reg_output | BIT(offset);
  

•   else
  

•           val = info->reg_output & ~BIT(offset);
  

•   ret = fxl6408_write(dev, REG_OUT_STATE, val);
  

•   if (ret < 0)
  

•           return ret;
  

•   info->reg_output = val;
  

•   return 0;
  

+}

+static int fxl6408_set_direction(struct udevice *dev, uint offset,

•                            enum io_direction dir)
  

+{

•   struct fxl6408_info *info = dev_get_plat(dev);
  

•   u8 val;
  

•   int ret;
  

•   if (dir == DIR_IN)
  

•           val = info->reg_io_dir & ~BIT(offset);
  

•   else
  

•           val = info->reg_io_dir | BIT(offset);
  

•   ret = fxl6408_write(dev, REG_IO_DIR, val);
  

•   if (ret < 0)
  

•           return ret;
  

•   info->reg_io_dir = val;
  

•   return 0;
  

+}

+static int fxl6408_direction_input(struct udevice *dev, uint offset) +{

•   return fxl6408_set_direction(dev, offset, DIR_IN);
  

+}

+static int fxl6408_direction_output(struct udevice *dev, uint offset, int value) +{

•   int ret;
  

•   /* Configure output value */
  

•   ret = fxl6408_set_value(dev, offset, value);
  

•   if (ret < 0)
  

•           return ret;
  

•   /* Configure direction as output */
  

•   fxl6408_set_direction(dev, offset, DIR_OUT);
  

•   return 0;
  

+}

+static int fxl6408_get_function(struct udevice *dev, uint offset) +{

•   if (fxl6408_is_output(dev, offset))
  

•           return GPIOF_OUTPUT;
  

•   else
  

•           return GPIOF_INPUT;
  

+}

+static int fxl6408_xlate(struct udevice *dev, struct gpio_desc *desc,

•                    struct ofnode_phandle_args *args)
  

+{

•   desc->offset = args->args[0];
  

•   desc->flags = args->args[1] & GPIO_ACTIVE_LOW ? GPIOD_ACTIVE_LOW : 0;
  

•   return 0;
  

+}

+static const struct dm_gpio_ops fxl6408_ops = {

•   .direction_input        = fxl6408_direction_input,
  

•   .direction_output       = fxl6408_direction_output,
  

•   .get_value              = fxl6408_get_value,
  

•   .set_value              = fxl6408_set_value,
  

•   .get_function           = fxl6408_get_function,
  

•   .xlate                  = fxl6408_xlate,
  

+};

+static int fxl6408_probe(struct udevice *dev) +{

•   struct fxl6408_info *info = dev_get_plat(dev);
  

•   struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
  

•   char name[32], label[32], *str;
  

•   int addr;
  

•   int ret;
  

•   int size;
  

•   const u8 *tmp;
  

•   u32 val32;
  

•   addr = dev_read_addr(dev);
  

•   if (addr == 0)
  

•           return -EINVAL;
  

•   info->addr = addr;
  

•   /*
  

•    * Check the device ID register to see if it's responding.
  

•    * This also clears RST_INT as a side effect, so we won't get
  

•    * the "we've been power cycled" interrupt once interrupts
  

•    * being enabled.
  

•    */
  

•   ret = fxl6408_read(dev, REG_DEVID_CTRL);
  

•   if (ret < 0) {
  

•           dev_err(dev, "FXL6408 probe returned %d\n", ret);
  

•           return ret;
  

•   }
  

•   if ((ret & MF_ID_MASK) >> MF_ID_SHIFT != MF_ID_FAIRCHILD) {
  

•           dev_err(dev, "FXL6408 probe: wrong Manufacturer's ID: 0x%02x\n", ret);
  

•           return -ENXIO;
  

•   }
  

•   info->device_id = ret;
  

•   /*
  

•    * Disable High-Z of outputs, so that the OUTPUT updates
  

•    * actually take effect.
  

•    */
  

•   ret = fxl6408_write(dev, REG_OUT_HIGH_Z, (u8)0);
  

•   if (ret < 0) {
  

•           dev_err(dev, "Error writing High-Z register\n");
  

•           return ret;
  

•   }
  

•   /*
  

•    * If configured, set initial output state and direction,
  

•    * otherwise read them from the chip.
  

•    */
  

•   if (dev_read_u32(dev, "initial_io_dir", &val32)) {
  

•           ret = fxl6408_read(dev, REG_IO_DIR);
  

•           if (ret < 0) {
  

•                   dev_err(dev, "Error reading direction register\n");
  

•                   return ret;
  

•           }
  

•           info->reg_io_dir = ret;
  

•   } else {
  

•           info->reg_io_dir = val32 & 0xFF;
  

•           ret = fxl6408_write(dev, REG_IO_DIR, info->reg_io_dir);
  

•           if (ret < 0) {
  

•                   dev_err(dev, "Error setting direction register\n");
  

•                   return ret;
  

•           }
  

•   }
  

•   if (dev_read_u32(dev, "initial_output", &val32)) {
  

•           ret = fxl6408_read(dev, REG_OUT_STATE);
  

•           if (ret < 0) {
  

•                   dev_err(dev, "Error reading output register\n");
  

•                   return ret;
  

•           }
  

•           info->reg_output = ret;
  

•   } else {
  

•           info->reg_output = val32 & 0xFF;
  

•           ret = fxl6408_write(dev, REG_OUT_STATE, info->reg_output);
  

•           if (ret < 0) {
  

•                   dev_err(dev, "Error setting output register\n");
  

•                   return ret;
  

•           }
  

•   }
  

•   tmp = dev_read_prop(dev, "label", &size);
  

•   if (tmp) {
  

•           size = min(size, (int)sizeof(label) - 1);
  

•           memcpy(label, tmp, size);
  

•           label[size] = '\0';
  

•           snprintf(name, sizeof(name), "%s@%x_", label, info->addr);
  

•   } else {
  

•           snprintf(name, sizeof(name), "gpio@%x_", info->addr);
  

•   }
  

•   str = strdup(name);
  

•   if (!str)
  

•           return -ENOMEM;
  

•   uc_priv->bank_name = str;
  

•   uc_priv->gpio_count = dev_get_driver_data(dev);
  

•   uc_priv->gpio_base = -1;
  

•   dev_dbg(dev, "%s (FW rev. %ld) is ready\n", str,
  

That's one l too much in the %ld which my gcc 9.2-2019.12 (arm-9.10)) 9.2.1 20191025 complains as follows:

In file included from drivers/gpio/gpio-fxl6408.c:36: drivers/gpio/gpio-fxl6408.c: In function ‘fxl6408_probe’: drivers/gpio/gpio-fxl6408.c:348:15: warning: format ‘%ld’ expects argument of type ‘long int’, but argument 3 has type ‘int’ [-Wformat=] 348 | dev_dbg(dev, "%s (FW rev. %ld) is ready\n", str, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 349 | (info->device_id & MF_ID_MASK) >> MF_ID_SHIFT); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | | | int include/dm/device_compat.h:50:10: note: in definition of macro ‘dev_printk_emit’ 50 | printf(fmt, ##__VA_ARGS__); \ | ^~~ include/dm/device_compat.h:117:2: note: in expansion of macro ‘__dev_printk’ 117 | __dev_printk(LOGL_DEBUG, dev, fmt, ##__VA_ARGS__) | ^~~~~~~~~~~~ drivers/gpio/gpio-fxl6408.c:348:2: note: in expansion of macro ‘dev_dbg’ 348 | dev_dbg(dev, "%s (FW rev. %ld) is ready\n", str, | ^~~~~~~ drivers/gpio/gpio-fxl6408.c:348:30: note: format string is defined here 348 | dev_dbg(dev, "%s (FW rev. %ld) is ready\n", str, | ~~^ | | | long int | %d

...

•           (info->device_id & MF_ID_MASK) >> MF_ID_SHIFT);
  

•   return 0;
  

+}

+static const struct udevice_id fxl6408_ids[] = {

•   { .compatible = "fcs,fxl6408", .data = 8 },
  

•   { }
  

+};

+U_BOOT_DRIVER(fxl6408_gpio) = {

•   .name = "fxl6408_gpio",
  

•   .id = UCLASS_GPIO,
  

•   .ops = &fxl6408_ops,
  

•   .probe = fxl6408_probe,
  

•   .of_match = fxl6408_ids,
  

•   .plat_auto = sizeof(struct fxl6408_info),
  

+};

Cheers

Marcel