openwrtv4/target/linux/ar71xx/patches-4.1/451-gpio-74x164-improve-platform-device-support.patch

--- 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