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--- a/drivers/gpio/gpio-74x164.c
+++ b/drivers/gpio/gpio-74x164.c
@@ -12,6 +12,7 @@
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/spi/spi.h>
+#include <linux/spi/74x164.h>
#include <linux/gpio.h>
#include <linux/of_gpio.h>
#include <linux/slab.h>
@@ -107,8 +108,18 @@ static int gen_74x164_direction_output(s
static int gen_74x164_probe(struct spi_device *spi)
{
struct gen_74x164_chip *chip;
+ struct gen_74x164_chip_platform_data *pdata;
+ struct device_node *np;
int ret;
+ pdata = spi->dev.platform_data;
+ np = spi->dev.of_node;
+
+ if (!np && !pdata) {
+ dev_err(&spi->dev, "No configuration data available.\n");
+ return -EINVAL;
+ }
+
/*
* bits_per_word cannot be configured in platform data
*/
@@ -130,18 +141,28 @@ static int gen_74x164_probe(struct spi_d
chip->gpio_chip.set = gen_74x164_set_value;
chip->gpio_chip.base = -1;
- if (of_property_read_u32(spi->dev.of_node, "registers-number",
- &chip->registers)) {
- dev_err(&spi->dev,
- "Missing registers-number property in the DT.\n");
- return -EINVAL;
+ if (np) {
+ if (of_property_read_u32(spi->dev.of_node, "registers-number", &chip->registers)) {
+ dev_err(&spi->dev, "Missing registers-number property in the DT.\n");
+ ret = -EINVAL;
+ goto exit_destroy;
+ }
+ } else if (pdata) {
+ chip->gpio_chip.base = pdata->base;
+ chip->registers = pdata->num_registers;
}
+ if (!chip->registers)
+ chip->registers = 1;
+
chip->gpio_chip.ngpio = GEN_74X164_NUMBER_GPIOS * chip->registers;
chip->buffer = devm_kzalloc(&spi->dev, chip->registers, GFP_KERNEL);
if (!chip->buffer)
return -ENOMEM;
+ if (pdata && pdata->init_data)
+ memcpy(chip->buffer, pdata->init_data, chip->registers);
+
chip->gpio_chip.can_sleep = true;
chip->gpio_chip.dev = &spi->dev;
chip->gpio_chip.owner = THIS_MODULE;
@@ -174,17 +195,19 @@ static int gen_74x164_remove(struct spi_
return 0;
}
+#ifdef CONFIG_OF
static const struct of_device_id gen_74x164_dt_ids[] = {
{ .compatible = "fairchild,74hc595" },
{},
};
MODULE_DEVICE_TABLE(of, gen_74x164_dt_ids);
+#endif /* CONFIG_OF */
static struct spi_driver gen_74x164_driver = {
.driver = {
.name = "74x164",
.owner = THIS_MODULE,
- .of_match_table = gen_74x164_dt_ids,
+ .of_match_table = of_match_ptr(gen_74x164_dt_ids),
},
.probe = gen_74x164_probe,
.remove = gen_74x164_remove,
--- /dev/null
+++ b/include/linux/spi/74x164.h
@@ -0,0 +1,13 @@
+#ifndef LINUX_SPI_74X164_H
+#define LINUX_SPI_74X164_H
+
+struct gen_74x164_chip_platform_data {
+ /* number assigned to the first GPIO */
+ unsigned base;
+ /* number of chained registers */
+ unsigned num_registers;
+ /* address of a buffer containing initial data */
+ u8 *init_data;
+};
+
+#endif
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -941,7 +941,7 @@ menu "SPI GPIO expanders"
config GPIO_74X164
tristate "74x164 serial-in/parallel-out 8-bits shift register"
- depends on SPI_MASTER && OF
+ depends on SPI_MASTER
help
Driver for 74x164 compatible serial-in/parallel-out 8-outputs
shift registers. This driver can be used to provide access
|
