[PATCH 5.10 41/73] serial: max310x: use regmap methods for SPI batch operations

From: Sasha Levin
Date: Wed Mar 13 2024 - 13:50:20 EST


From: Cosmin Tanislav <cosmin.tanislav@xxxxxxxxxx>

[ Upstream commit 285e76fc049c4d32c772eea9460a7ef28a193802 ]

The SPI batch read/write operations can be implemented as simple
regmap raw read and write, which will also try to do a gather
write just as it is done here.

Use the regmap raw read and write methods.

Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Signed-off-by: Cosmin Tanislav <cosmin.tanislav@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220605144659.4169853-2-demonsingur@xxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Stable-dep-of: b35f8dbbce81 ("serial: max310x: prevent infinite while() loop in port startup")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/tty/serial/max310x.c | 36 ++++++++----------------------------
1 file changed, 8 insertions(+), 28 deletions(-)

diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c
index 8d42c537ee5ea..c0fa4ad104774 100644
--- a/drivers/tty/serial/max310x.c
+++ b/drivers/tty/serial/max310x.c
@@ -263,8 +263,6 @@ struct max310x_one {
struct work_struct md_work;
struct work_struct rs_work;

- u8 wr_header;
- u8 rd_header;
u8 rx_buf[MAX310X_FIFO_SIZE];
};
#define to_max310x_port(_port) \
@@ -635,32 +633,18 @@ static s32 max310x_set_ref_clk(struct device *dev, struct max310x_port *s,

static void max310x_batch_write(struct uart_port *port, u8 *txbuf, unsigned int len)
{
- struct max310x_one *one = to_max310x_port(port);
- struct spi_transfer xfer[] = {
- {
- .tx_buf = &one->wr_header,
- .len = sizeof(one->wr_header),
- }, {
- .tx_buf = txbuf,
- .len = len,
- }
- };
- spi_sync_transfer(to_spi_device(port->dev), xfer, ARRAY_SIZE(xfer));
+ struct max310x_port *s = dev_get_drvdata(port->dev);
+ u8 reg = port->iobase + MAX310X_THR_REG;
+
+ regmap_raw_write(s->regmap, reg, txbuf, len);
}

static void max310x_batch_read(struct uart_port *port, u8 *rxbuf, unsigned int len)
{
- struct max310x_one *one = to_max310x_port(port);
- struct spi_transfer xfer[] = {
- {
- .tx_buf = &one->rd_header,
- .len = sizeof(one->rd_header),
- }, {
- .rx_buf = rxbuf,
- .len = len,
- }
- };
- spi_sync_transfer(to_spi_device(port->dev), xfer, ARRAY_SIZE(xfer));
+ struct max310x_port *s = dev_get_drvdata(port->dev);
+ u8 reg = port->iobase + MAX310X_RHR_REG;
+
+ regmap_raw_read(s->regmap, reg, rxbuf, len);
}

static void max310x_handle_rx(struct uart_port *port, unsigned int rxlen)
@@ -1390,10 +1374,6 @@ static int max310x_probe(struct device *dev, const struct max310x_devtype *devty
INIT_WORK(&s->p[i].md_work, max310x_md_proc);
/* Initialize queue for changing RS485 mode */
INIT_WORK(&s->p[i].rs_work, max310x_rs_proc);
- /* Initialize SPI-transfer buffers */
- s->p[i].wr_header = (s->p[i].port.iobase + MAX310X_THR_REG) |
- MAX310X_WRITE_BIT;
- s->p[i].rd_header = (s->p[i].port.iobase + MAX310X_RHR_REG);

/* Register port */
ret = uart_add_one_port(&max310x_uart, &s->p[i].port);
--
2.43.0