On 4/20/23 05:13, Herve Codina wrote:
The Renesas X9250 integrates four digitally controlled potentiometers.
On each potentiometer, the X9250T has a 100 kOhms total resistance and
the X9250U has a 50 kOhms total resistance.
Signed-off-by: Herve Codina <herve.codina@xxxxxxxxxxx>
Hi,
Looks perfect! Just one small comment.
+static int x9250_write8(struct x9250 *x9250, u8 cmd, u8 val)
+{
+ struct spi_transfer xfer = {
+ .tx_buf = &x9250->spi_tx_buf,
+ .len = 3,
+ };
+ int ret;
+
+ BUILD_BUG_ON(sizeof(x9250->spi_tx_buf) < 3);
+
+ mutex_lock(&x9250->lock);
+
+ x9250->spi_tx_buf[0] = 0x50;
The 0x50 shows up as a magic constant in multiple places, a define for
it would be nice.
+ x9250->spi_tx_buf[1] = cmd;
+ x9250->spi_tx_buf[2] = val;
+
+ ret = spi_sync_transfer(x9250->spi, &xfer, 1);
+
+ mutex_unlock(&x9250->lock);
+
+ return ret;
+}
