serial: 8250: Change dl_read/write to handle value as u32

Divisor latch read/write functions currently handle the value is int.
As the value is related to HW context, u32 makes much more sense than a
signed type.

While at it, name the parameters in the callback signature.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230511121029.13128-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h
index 1e8fe44..5418708 100644 (file)
--- a/drivers/tty/serial/8250/8250.h
+++ b/drivers/tty/serial/8250/8250.h
@@ -167,12 +167,12 @@ static unsigned int __maybe_unused serial_icr_read(struct uart_8250_port *up,
 
 void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p);
 
-static inline int serial_dl_read(struct uart_8250_port *up)
+static inline u32 serial_dl_read(struct uart_8250_port *up)
 {
        return up->dl_read(up);
 }
 
-static inline void serial_dl_write(struct uart_8250_port *up, int value)
+static inline void serial_dl_write(struct uart_8250_port *up, u32 value)
 {
        up->dl_write(up, value);
 }

diff --git a/drivers/tty/serial/8250/8250_em.c b/drivers/tty/serial/8250/8250_em.c
index 25a9ecf..ef5019e 100644 (file)
--- a/drivers/tty/serial/8250/8250_em.c
+++ b/drivers/tty/serial/8250/8250_em.c
@@ -139,12 +139,12 @@ static void serial8250_em_serial_out(struct uart_port *p, int offset, int value)
        }
 }
 
-static int serial8250_em_serial_dl_read(struct uart_8250_port *up)
+static u32 serial8250_em_serial_dl_read(struct uart_8250_port *up)
 {
        return serial_in(up, UART_DLL_EM) | serial_in(up, UART_DLM_EM) << 8;
 }
 
-static void serial8250_em_serial_dl_write(struct uart_8250_port *up, int value)
+static void serial8250_em_serial_dl_write(struct uart_8250_port *up, u32 value)
 {
        serial_out(up, UART_DLL_EM, value & 0xff);
        serial_out(up, UART_DLM_EM, value >> 8 & 0xff);

diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index fe8d79c..344bd44 100644 (file)
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -325,7 +325,7 @@ static const struct serial8250_config uart_config[] = {
 };
 
 /* Uart divisor latch read */
-static int default_serial_dl_read(struct uart_8250_port *up)
+static u32 default_serial_dl_read(struct uart_8250_port *up)
 {
        /* Assign these in pieces to truncate any bits above 7.  */
        unsigned char dll = serial_in(up, UART_DLL);
@@ -335,7 +335,7 @@ static int default_serial_dl_read(struct uart_8250_port *up)
 }
 
 /* Uart divisor latch write */
-static void default_serial_dl_write(struct uart_8250_port *up, int value)
+static void default_serial_dl_write(struct uart_8250_port *up, u32 value)
 {
        serial_out(up, UART_DLL, value & 0xff);
        serial_out(up, UART_DLM, value >> 8 & 0xff);
@@ -389,12 +389,12 @@ void au_serial_out(struct uart_port *p, int offset, int value)
 }
 
 /* Au1x00 haven't got a standard divisor latch */
-static int au_serial_dl_read(struct uart_8250_port *up)
+static u32 au_serial_dl_read(struct uart_8250_port *up)
 {
        return __raw_readl(up->port.membase + 0x28);
 }
 
-static void au_serial_dl_write(struct uart_8250_port *up, int value)
+static void au_serial_dl_write(struct uart_8250_port *up, u32 value)
 {
        __raw_writel(value, up->port.membase + 0x28);
 }
@@ -847,7 +847,7 @@ static void disable_rsa(struct uart_8250_port *up)
 static int size_fifo(struct uart_8250_port *up)
 {
        unsigned char old_fcr, old_mcr, old_lcr;
-       unsigned short old_dl;
+       u32 old_dl;
        int count;
 
        old_lcr = serial_in(up, UART_LCR);

diff --git a/drivers/tty/serial/8250/8250_pxa.c b/drivers/tty/serial/8250/8250_pxa.c
index 795e551..28b341f 100644 (file)
--- a/drivers/tty/serial/8250/8250_pxa.c
+++ b/drivers/tty/serial/8250/8250_pxa.c
@@ -60,7 +60,7 @@ static const struct of_device_id serial_pxa_dt_ids[] = {
 MODULE_DEVICE_TABLE(of, serial_pxa_dt_ids);
 
 /* Uart divisor latch write */
-static void serial_pxa_dl_write(struct uart_8250_port *up, int value)
+static void serial_pxa_dl_write(struct uart_8250_port *up, u32 value)
 {
        unsigned int dll;
 

diff --git a/drivers/tty/serial/8250/8250_uniphier.c b/drivers/tty/serial/8250/8250_uniphier.c
index a2978ab..a405155 100644 (file)
--- a/drivers/tty/serial/8250/8250_uniphier.c
+++ b/drivers/tty/serial/8250/8250_uniphier.c
@@ -145,12 +145,12 @@ static void uniphier_serial_out(struct uart_port *p, int offset, int value)
  * The divisor latch register exists at different address.
  * Override dl_read/write callbacks.
  */
-static int uniphier_serial_dl_read(struct uart_8250_port *up)
+static u32 uniphier_serial_dl_read(struct uart_8250_port *up)
 {
        return readl(up->port.membase + UNIPHIER_UART_DLR);
 }
 
-static void uniphier_serial_dl_write(struct uart_8250_port *up, int value)
+static void uniphier_serial_dl_write(struct uart_8250_port *up, u32 value)
 {
        writel(value, up->port.membase + UNIPHIER_UART_DLR);
 }

diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h
index 6f78f30..7b5d558 100644 (file)
--- a/include/linux/serial_8250.h
+++ b/include/linux/serial_8250.h
@@ -129,8 +129,8 @@ struct uart_8250_port {
        const struct uart_8250_ops *ops;
 
        /* 8250 specific callbacks */
-       int                     (*dl_read)(struct uart_8250_port *);
-       void                    (*dl_write)(struct uart_8250_port *, int);
+       u32                     (*dl_read)(struct uart_8250_port *up);
+       void                    (*dl_write)(struct uart_8250_port *up, u32 value);
 
        struct uart_8250_em485 *em485;
        void                    (*rs485_start_tx)(struct uart_8250_port *);