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i2c: pcf8575: Add support for 8 bit I2C IO expanders (like pca8574)

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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>
Reviewed-by: Heiko Schocher <hs@denx.de>
This commit is contained in:
Lukasz Majewski 2021-06-07 14:26:34 +02:00 committed by Tom Rini
parent 0119c91052
commit 2132fce7e1
1 changed files with 19 additions and 21 deletions
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40
drivers/gpio/pcf8575_gpio.c
View File

@ -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 },
{ }
};