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-rw-r--r--drivers/gpio/gpio-74x164.c47
1 files changed, 15 insertions, 32 deletions
diff --git a/drivers/gpio/gpio-74x164.c b/drivers/gpio/gpio-74x164.c
index b0939e0ff0b9..54a4147fba52 100644
--- a/drivers/gpio/gpio-74x164.c
+++ b/drivers/gpio/gpio-74x164.c
@@ -23,6 +23,13 @@ struct gen_74x164_chip {
struct gpio_chip gpio_chip;
struct mutex lock;
u32 registers;
+ /*
+ * Since the registers are chained, every byte sent will make
+ * the previous byte shift to the next register in the
+ * chain. Thus, the first byte sent will end up in the last
+ * register at the end of the transfer. So, to have a logical
+ * numbering, store the bytes in reverse order.
+ */
u8 buffer[0];
};
@@ -33,43 +40,19 @@ static struct gen_74x164_chip *gpio_to_74x164_chip(struct gpio_chip *gc)
static int __gen_74x164_write_config(struct gen_74x164_chip *chip)
{
- struct spi_device *spi = to_spi_device(chip->gpio_chip.parent);
- struct spi_message message;
- struct spi_transfer *msg_buf;
- int i, ret = 0;
-
- msg_buf = kzalloc(chip->registers * sizeof(struct spi_transfer),
- GFP_KERNEL);
- if (!msg_buf)
- return -ENOMEM;
-
- spi_message_init(&message);
+ struct spi_transfer xfer = {
+ .tx_buf = chip->buffer,
+ .len = chip->registers,
+ };
- /*
- * Since the registers are chained, every byte sent will make
- * the previous byte shift to the next register in the
- * chain. Thus, the first byte send will end up in the last
- * register at the end of the transfer. So, to have a logical
- * numbering, send the bytes in reverse order so that the last
- * byte of the buffer will end up in the last register.
- */
- for (i = chip->registers - 1; i >= 0; i--) {
- msg_buf[i].tx_buf = chip->buffer + i;
- msg_buf[i].len = sizeof(u8);
- spi_message_add_tail(msg_buf + i, &message);
- }
-
- ret = spi_sync(spi, &message);
-
- kfree(msg_buf);
-
- return ret;
+ return spi_sync_transfer(to_spi_device(chip->gpio_chip.parent),
+ &xfer, 1);
}
static int gen_74x164_get_value(struct gpio_chip *gc, unsigned offset)
{
struct gen_74x164_chip *chip = gpio_to_74x164_chip(gc);
- u8 bank = offset / 8;
+ u8 bank = chip->registers - 1 - offset / 8;
u8 pin = offset % 8;
int ret;
@@ -84,7 +67,7 @@ static void gen_74x164_set_value(struct gpio_chip *gc,
unsigned offset, int val)
{
struct gen_74x164_chip *chip = gpio_to_74x164_chip(gc);
- u8 bank = offset / 8;
+ u8 bank = chip->registers - 1 - offset / 8;
u8 pin = offset % 8;
mutex_lock(&chip->lock);