gpio: 74x164: Allocate buffer with gen_74x164_chip
By moving the internal buffer to the end of struct gen_74x164_chip and
converting it from a pointer to a zero-sized array, it can be allocated
together with gen_74x164_chip, reducing the number of managed
allocations.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpio-74x164.c b/drivers/gpio/gpio-74x164.c
index fb55530..b0939e0 100644
--- a/drivers/gpio/gpio-74x164.c
+++ b/drivers/gpio/gpio-74x164.c
@@ -20,10 +20,10 @@
#define GEN_74X164_NUMBER_GPIOS 8
struct gen_74x164_chip {
- u8 *buffer;
struct gpio_chip gpio_chip;
struct mutex lock;
u32 registers;
+ u8 buffer[0];
};
static struct gen_74x164_chip *gpio_to_74x164_chip(struct gpio_chip *gc)
@@ -107,6 +107,7 @@
static int gen_74x164_probe(struct spi_device *spi)
{
struct gen_74x164_chip *chip;
+ u32 nregs;
int ret;
/*
@@ -118,7 +119,14 @@
if (ret < 0)
return ret;
- chip = devm_kzalloc(&spi->dev, sizeof(*chip), GFP_KERNEL);
+ 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;
+ }
+
+ chip = devm_kzalloc(&spi->dev, sizeof(*chip) + nregs, GFP_KERNEL);
if (!chip)
return -ENOMEM;
@@ -130,17 +138,8 @@
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;
- }
-
+ chip->registers = nregs;
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;
chip->gpio_chip.can_sleep = true;
chip->gpio_chip.parent = &spi->dev;