openwrtv3/target/linux/ar71xx/patches-4.9/451-gpio-74x164-improve-platform-device-support.patch
Felix Fietkau 645b163cfc ar71xx: fix regression in 74x164 initialization with 4.9
The memcpy of the init data relies on chip->registers to be initialized,
which only happens later in the code. Move this initialization further
down to make it work.
This was breaking PCIe/USB on some MikroTik RouterBoard devices.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
2017-11-10 00:53:10 +01:00

119 lines
3.3 KiB
Diff

--- 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>
@@ -103,9 +104,16 @@ 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 = spi->dev.platform_data;
+ struct device_node *np = spi->dev.of_node;
u32 nregs;
int ret;
+ if (!np && !pdata) {
+ dev_err(&spi->dev, "No configuration data available.\n");
+ return -EINVAL;
+ }
+
/*
* bits_per_word cannot be configured in platform data
*/
@@ -115,12 +123,15 @@ static int gen_74x164_probe(struct spi_d
if (ret < 0)
return ret;
- if (of_property_read_u32(spi->dev.of_node, "registers-number",
- &nregs)) {
- dev_err(&spi->dev,
- "Missing registers-number property in the DT.\n");
- return -EINVAL;
- }
+ if (np) {
+ if (of_property_read_u32(np, "registers-number", &nregs)) {
+ dev_err(&spi->dev,
+ "Missing registers-number property in the DT.\n");
+ return -EINVAL;
+ }
+ } else if (pdata) {
+ nregs = pdata->num_registers;
+ }
chip = devm_kzalloc(&spi->dev, sizeof(*chip) + nregs, GFP_KERNEL);
if (!chip)
@@ -133,7 +144,11 @@ static int gen_74x164_probe(struct spi_d
chip->gpio_chip.get = gen_74x164_get_value;
chip->gpio_chip.set = gen_74x164_set_value;
chip->gpio_chip.set_multiple = gen_74x164_set_multiple;
- chip->gpio_chip.base = -1;
+ if (np)
+ chip->gpio_chip.base = -1;
+ else if (pdata)
+ chip->gpio_chip.base = pdata->base;
+
chip->registers = nregs;
chip->gpio_chip.ngpio = GEN_74X164_NUMBER_GPIOS * chip->registers;
@@ -142,6 +157,9 @@ static int gen_74x164_probe(struct spi_d
chip->gpio_chip.parent = &spi->dev;
chip->gpio_chip.owner = THIS_MODULE;
+ if (pdata && pdata->init_data)
+ memcpy(chip->buffer, pdata->init_data, chip->registers);
+
mutex_init(&chip->lock);
ret = __gen_74x164_write_config(chip);
@@ -170,17 +188,19 @@ 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" },
{ .compatible = "nxp,74lvc594" },
{},
};
MODULE_DEVICE_TABLE(of, gen_74x164_dt_ids);
+#endif
static struct spi_driver gen_74x164_driver = {
.driver = {
.name = "74x164",
- .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
@@ -1154,7 +1154,6 @@ menu "SPI GPIO expanders"
config GPIO_74X164
tristate "74x164 serial-in/parallel-out 8-bits shift register"
- depends on OF_GPIO
help
Driver for 74x164 compatible serial-in/parallel-out 8-outputs
shift registers. This driver can be used to provide access