This patch add support for using NXP's pca8574 I2C IO expander, which has only 8 IO lines.

After this change the .data member's information from struct udevice_id are used to either sent one or two bytes.

Moreover, the '_le16' suffix from pcf8575_i2c_{write|read}_le16() functions have been removed as now we also sent 8 bit data.

Signed-off-by: Lukasz Majewski lukma@denx.de

---

drivers/gpio/pcf8575_gpio.c | 40 ++++++++++++++++++------------------- 1 file changed, 19 insertions(+), 21 deletions(-)

diff --git a/drivers/gpio/pcf8575_gpio.c b/drivers/gpio/pcf8575_gpio.c index bae9695f28b1..d5930d941fc0 100644 --- a/drivers/gpio/pcf8575_gpio.c +++ b/drivers/gpio/pcf8575_gpio.c @@ -12,15 +12,9 @@ * * Copyright (C) 2007 David Brownell * - */ - -/* - * NOTE: The driver and devicetree bindings are borrowed from Linux - * Kernel, but driver does not support all PCF857x devices. It currently - * supports PCF8575 16-bit expander by TI and NXP. + * Add support for 8 bit expanders - like pca8574 + * Copyright (C) 2021 Lukasz Majewski - DENX Software Engineering * - * TODO(vigneshr@ti.com): - * Support 8 bit PCF857x compatible expanders. */

#include <common.h> @@ -49,15 +43,15 @@ struct pcf8575_chip { unsigned int out; /* software latch */ };

-/* Read/Write to 16-bit I/O expander */ +/* Read/Write to I/O expander */

-static int pcf8575_i2c_write_le16(struct udevice *dev, unsigned int word) +static int pcf8575_i2c_write(struct udevice *dev, unsigned int word) { struct dm_i2c_chip *chip = dev_get_parent_plat(dev); u8 buf[2] = { word & 0xff, word >> 8, }; int ret;

- ret = dm_i2c_write(dev, 0, buf, 2); + ret = dm_i2c_write(dev, 0, buf, dev_get_driver_data(dev)); if (ret) printf("%s i2c write failed to addr %x\n", __func__, chip->chip_addr); @@ -65,13 +59,13 @@ static int pcf8575_i2c_write_le16(struct udevice *dev, unsigned int word) return ret; }

-static int pcf8575_i2c_read_le16(struct udevice *dev) +static int pcf8575_i2c_read(struct udevice *dev) { struct dm_i2c_chip *chip = dev_get_parent_plat(dev); - u8 buf[2]; + u8 buf[2] = {0x00, 0x00}; int ret;

- ret = dm_i2c_read(dev, 0, buf, 2); + ret = dm_i2c_read(dev, 0, buf, dev_get_driver_data(dev)); if (ret) { printf("%s i2c read failed from addr %x\n", __func__, chip->chip_addr); @@ -87,7 +81,7 @@ static int pcf8575_direction_input(struct udevice *dev, unsigned offset) int status;

plat->out |= BIT(offset); - status = pcf8575_i2c_write_le16(dev, plat->out); + status = pcf8575_i2c_write(dev, plat->out);

return status; } @@ -103,7 +97,7 @@ static int pcf8575_direction_output(struct udevice *dev, else plat->out &= ~BIT(offset);

- ret = pcf8575_i2c_write_le16(dev, plat->out); + ret = pcf8575_i2c_write(dev, plat->out);

return ret; } @@ -112,7 +106,7 @@ static int pcf8575_get_value(struct udevice *dev, unsigned int offset) { int value;

- value = pcf8575_i2c_read_le16(dev); + value = pcf8575_i2c_read(dev);

return (value < 0) ? value : ((value & BIT(offset)) >> offset); } @@ -130,8 +124,11 @@ static int pcf8575_ofdata_plat(struct udevice *dev)

int n_latch;

- uc_priv->gpio_count = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev), - "gpio-count", 16); + /* + * Number of pins depends on the expander device and is specified + * in the struct udevice_id (as in the Linue kernel). + */ + uc_priv->gpio_count = dev_get_driver_data(dev) * 8; uc_priv->bank_name = fdt_getprop(gd->fdt_blob, dev_of_offset(dev), "gpio-bank-name", NULL); if (!uc_priv->bank_name) @@ -163,8 +160,9 @@ static const struct dm_gpio_ops pcf8575_gpio_ops = { };

static const struct udevice_id pcf8575_gpio_ids[] = { - { .compatible = "nxp,pcf8575" }, - { .compatible = "ti,pcf8575" }, + { .compatible = "nxp,pcf8575", .data = 2 }, + { .compatible = "ti,pcf8575", .data = 2 }, + { .compatible = "nxp,pca8574", .data = 1 }, { } };