[PATCH 16/18] tty: serial: samsung: shrink the clock selection to 8 clocks

From: Tudor Ambarus
Date: Wed Jan 10 2024 - 05:25:46 EST


<linux/serial_s3c.h> provides a clock selection pool of maximum 4 clocks.
Update the driver to consider a pool selection of maximum 8 clocks. The
final scope is to reduce the memory footprint of
``struct s3c24xx_uart_info``.

Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxx>
---
drivers/tty/serial/samsung_tty.c | 22 +++++++++++-----------
1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c
index 436739cf9225..5df2bcebf9fb 100644
--- a/drivers/tty/serial/samsung_tty.c
+++ b/drivers/tty/serial/samsung_tty.c
@@ -81,11 +81,11 @@ struct s3c24xx_uart_info {
unsigned long tx_fifomask;
unsigned long tx_fifoshift;
unsigned long tx_fifofull;
- unsigned int def_clk_sel;
- unsigned long num_clks;
unsigned long clksel_mask;
unsigned long clksel_shift;
unsigned long ucon_mask;
+ u8 def_clk_sel;
+ u8 num_clks;
u8 iotype;

/* uart port features */
@@ -1339,7 +1339,7 @@ static void s3c24xx_serial_pm(struct uart_port *port, unsigned int level,

#define MAX_CLK_NAME_LENGTH 15

-static inline int s3c24xx_serial_getsource(struct uart_port *port)
+static inline u8 s3c24xx_serial_getsource(struct uart_port *port)
{
const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
u32 ucon;
@@ -1352,8 +1352,7 @@ static inline int s3c24xx_serial_getsource(struct uart_port *port)
return ucon >> info->clksel_shift;
}

-static void s3c24xx_serial_setsource(struct uart_port *port,
- unsigned int clk_sel)
+static void s3c24xx_serial_setsource(struct uart_port *port, u8 clk_sel)
{
const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
u32 ucon;
@@ -1372,14 +1371,15 @@ static void s3c24xx_serial_setsource(struct uart_port *port,

static unsigned int s3c24xx_serial_getclk(struct s3c24xx_uart_port *ourport,
unsigned int req_baud, struct clk **best_clk,
- unsigned int *clk_num)
+ u8 *clk_num)
{
const struct s3c24xx_uart_info *info = ourport->info;
struct clk *clk;
unsigned long rate;
- unsigned int cnt, baud, quot, best_quot = 0;
+ unsigned int baud, quot, best_quot = 0;
char clkname[MAX_CLK_NAME_LENGTH];
int calc_deviation, deviation = (1 << 30) - 1;
+ u8 cnt;

for (cnt = 0; cnt < info->num_clks; cnt++) {
/* Keep selected clock if provided */
@@ -1472,9 +1472,10 @@ static void s3c24xx_serial_set_termios(struct uart_port *port,
struct s3c24xx_uart_port *ourport = to_ourport(port);
struct clk *clk = ERR_PTR(-EINVAL);
unsigned long flags;
- unsigned int baud, quot, clk_sel = 0;
+ unsigned int baud, quot;
unsigned int udivslot = 0;
u32 ulcon, umcon;
+ u8 clk_sel = 0;

/*
* We don't support modem control lines.
@@ -1775,10 +1776,9 @@ static int s3c24xx_serial_enable_baudclk(struct s3c24xx_uart_port *ourport)
struct device *dev = ourport->port.dev;
const struct s3c24xx_uart_info *info = ourport->info;
char clk_name[MAX_CLK_NAME_LENGTH];
- unsigned int clk_sel;
struct clk *clk;
- int clk_num;
int ret;
+ u8 clk_sel, clk_num;

clk_sel = ourport->cfg->clk_sel ? : info->def_clk_sel;
for (clk_num = 0; clk_num < info->num_clks; clk_num++) {
@@ -2286,9 +2286,9 @@ s3c24xx_serial_get_options(struct uart_port *port, int *baud,
{
struct clk *clk;
unsigned long rate;
- unsigned int clk_sel;
u32 ulcon, ucon, ubrdiv;
char clk_name[MAX_CLK_NAME_LENGTH];
+ u8 clk_sel;

ulcon = rd_regl(port, S3C2410_ULCON);
ucon = rd_regl(port, S3C2410_UCON);
--
2.43.0.472.g3155946c3a-goog