ar71xx: improve platform device support in the gpio-74x164 driver

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@39701 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 74 insertions, 0 deletions

diff --git a/target/linux/ar71xx/patches-3.10/451-gpio-74x164-improve-platform-device-support.patch b/target/linux/ar71xx/patches-3.10/451-gpio-74x164-improve-platform-device-support.patch
new file mode 100644
index 0000000000..b19bb85c85
--- /dev/null
+++ b/target/linux/ar71xx/patches-3.10/451-gpio-74x164-improve-platform-device-support.patch
@@ -0,0 +1,74 @@
+--- a/drivers/gpio/gpio-74x164.c
++++ b/drivers/gpio/gpio-74x164.c
+@@ -109,10 +109,14 @@ static int gen_74x164_probe(struct spi_d
+ {
+ 	struct gen_74x164_chip *chip;
+ 	struct gen_74x164_chip_platform_data *pdata;
++	struct device_node *np;
+ 	int ret;
+ 
+-	if (!spi->dev.of_node) {
+-		dev_err(&spi->dev, "No device tree data available.\n");
++	pdata = spi->dev.platform_data;
++	np = spi->dev.of_node;
++
++	if (!np && !pdata) {
++		dev_err(&spi->dev, "No configuration data available.\n");
+ 		return -EINVAL;
+ 	}
+ 
+@@ -129,7 +133,6 @@ static int gen_74x164_probe(struct spi_d
+ 	if (!chip)
+ 		return -ENOMEM;
+ 
+-	pdata = spi->dev.platform_data;
+ 	if (pdata && pdata->base)
+ 		chip->gpio_chip.base = pdata->base;
+ 	else
+@@ -146,12 +149,19 @@ static int gen_74x164_probe(struct spi_d
+ 	chip->gpio_chip.get = gen_74x164_get_value;
+ 	chip->gpio_chip.set = gen_74x164_set_value;
+ 
+-	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;
++	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->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) {
+@@ -159,6 +169,9 @@ static int gen_74x164_probe(struct spi_d
+ 		goto exit_destroy;
+ 	}
+ 
++	if (pdata && pdata->init_data)
++		memcpy(chip->buffer, pdata->init_data, chip->registers);
++
+ 	chip->gpio_chip.can_sleep = 1;
+ 	chip->gpio_chip.dev = &spi->dev;
+ 	chip->gpio_chip.owner = THIS_MODULE;
+--- a/include/linux/spi/74x164.h
++++ b/include/linux/spi/74x164.h
+@@ -4,6 +4,10 @@
+ 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