Re: [PATCH v9 1/6] serial: 8250: make saved LSR larger

From: Andy Shevchenko
Date: Tue Jun 28 2022 - 07:03:13 EST

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In reply to: Ilpo Järvinen: "[PATCH v9 1/6] serial: 8250: make saved LSR larger"
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On Fri, Jun 24, 2022 at 11:42:05PM +0300, Ilpo Järvinen wrote:
> DW flags address received as BIT(8) in LSR. In order to not lose that
> on read, enlarge lsr_saved_flags to u16.
>
> Adjust lsr/status variables and related call chains to use u16.
> Technically, some of these type conversion would not be needed but it
> doesn't hurt to be consistent.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
> ---
> drivers/tty/serial/8250/8250.h | 4 ++--
> drivers/tty/serial/8250/8250_exar.c | 2 +-
> drivers/tty/serial/8250/8250_fsl.c | 2 +-
> drivers/tty/serial/8250/8250_ingenic.c | 2 +-
> drivers/tty/serial/8250/8250_omap.c | 7 +++----
> drivers/tty/serial/8250/8250_port.c | 17 +++++++++--------
> include/linux/serial_8250.h | 6 +++---
> 7 files changed, 20 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h
> index b120da57c61f..0ff5688ba90c 100644
> --- a/drivers/tty/serial/8250/8250.h
> +++ b/drivers/tty/serial/8250/8250.h
> @@ -133,9 +133,9 @@ static inline void serial_out(struct uart_8250_port *up, int offset, int value)
> *
> * Returns LSR value or'ed with the preserved flags (if any).
> */
> -static inline unsigned int serial_lsr_in(struct uart_8250_port *up)
> +static inline u16 serial_lsr_in(struct uart_8250_port *up)
> {
> - unsigned int lsr = up->lsr_saved_flags;
> + u16 lsr = up->lsr_saved_flags;
>
> lsr |= serial_in(up, UART_LSR);
> up->lsr_saved_flags = lsr & LSR_SAVE_FLAGS;
> diff --git a/drivers/tty/serial/8250/8250_exar.c b/drivers/tty/serial/8250/8250_exar.c
> index 528779b40049..3d999eec4087 100644
> --- a/drivers/tty/serial/8250/8250_exar.c
> +++ b/drivers/tty/serial/8250/8250_exar.c
> @@ -195,11 +195,11 @@ static int xr17v35x_startup(struct uart_port *port)
>
> static void exar_shutdown(struct uart_port *port)
> {
> - unsigned char lsr;
> bool tx_complete = false;
> struct uart_8250_port *up = up_to_u8250p(port);
> struct circ_buf *xmit = &port->state->xmit;
> int i = 0;
> + u16 lsr;
>
> do {
> lsr = serial_in(up, UART_LSR);
> diff --git a/drivers/tty/serial/8250/8250_fsl.c b/drivers/tty/serial/8250/8250_fsl.c
> index 9c01c531349d..fd4005fcd0d6 100644
> --- a/drivers/tty/serial/8250/8250_fsl.c
> +++ b/drivers/tty/serial/8250/8250_fsl.c
> @@ -25,8 +25,8 @@
>
> int fsl8250_handle_irq(struct uart_port *port)
> {
> - unsigned char lsr, orig_lsr;
> unsigned long flags;
> + u16 lsr, orig_lsr;
> unsigned int iir;
> struct uart_8250_port *up = up_to_u8250p(port);
>
> diff --git a/drivers/tty/serial/8250/8250_ingenic.c b/drivers/tty/serial/8250/8250_ingenic.c
> index cff91aa03f29..2b2f5d8d24b9 100644
> --- a/drivers/tty/serial/8250/8250_ingenic.c
> +++ b/drivers/tty/serial/8250/8250_ingenic.c
> @@ -54,7 +54,7 @@ static void early_out(struct uart_port *port, int offset, uint8_t value)
>
> static void ingenic_early_console_putc(struct uart_port *port, unsigned char c)
> {
> - uint8_t lsr;
> + u16 lsr;
>
> do {
> lsr = early_in(port, UART_LSR);
> diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
> index ac8bfa042391..0dcecbbc3967 100644
> --- a/drivers/tty/serial/8250/8250_omap.c
> +++ b/drivers/tty/serial/8250/8250_omap.c
> @@ -1115,8 +1115,7 @@ static bool handle_rx_dma(struct uart_8250_port *up, unsigned int iir)
> return omap_8250_rx_dma(up);
> }
>
> -static unsigned char omap_8250_handle_rx_dma(struct uart_8250_port *up,
> - u8 iir, unsigned char status)
> +static u16 omap_8250_handle_rx_dma(struct uart_8250_port *up, u8 iir, u16 status)
> {
> if ((status & (UART_LSR_DR | UART_LSR_BI)) &&
> (iir & UART_IIR_RDI)) {
> @@ -1130,7 +1129,7 @@ static unsigned char omap_8250_handle_rx_dma(struct uart_8250_port *up,
> }
>
> static void am654_8250_handle_rx_dma(struct uart_8250_port *up, u8 iir,
> - unsigned char status)
> + u16 status)
> {
> /*
> * Queue a new transfer if FIFO has data.
> @@ -1164,7 +1163,7 @@ static int omap_8250_dma_handle_irq(struct uart_port *port)
> {
> struct uart_8250_port *up = up_to_u8250p(port);
> struct omap8250_priv *priv = up->port.private_data;
> - unsigned char status;
> + u16 status;
> u8 iir;
>
> serial8250_rpm_get(up);
> diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
> index c860f5964138..19c612d732cf 100644
> --- a/drivers/tty/serial/8250/8250_port.c
> +++ b/drivers/tty/serial/8250/8250_port.c
> @@ -1508,7 +1508,7 @@ static inline void __stop_tx(struct uart_8250_port *p)
> struct uart_8250_em485 *em485 = p->em485;
>
> if (em485) {
> - unsigned char lsr = serial_lsr_in(p);
> + u16 lsr = serial_lsr_in(p);
> u64 stop_delay = 0;
>
> if (!(lsr & UART_LSR_THRE))
> @@ -1565,7 +1565,7 @@ static inline void __start_tx(struct uart_port *port)
>
> if (serial8250_set_THRI(up)) {
> if (up->bugs & UART_BUG_TXEN) {
> - unsigned char lsr = serial_lsr_in(up);
> + u16 lsr = serial_lsr_in(up);
>
> if (lsr & UART_LSR_THRE)
> serial8250_tx_chars(up);
> @@ -1719,7 +1719,7 @@ static void serial8250_enable_ms(struct uart_port *port)
> serial8250_rpm_put(up);
> }
>
> -void serial8250_read_char(struct uart_8250_port *up, unsigned char lsr)
> +void serial8250_read_char(struct uart_8250_port *up, u16 lsr)
> {
> struct uart_port *port = &up->port;
> unsigned char ch;
> @@ -1788,7 +1788,7 @@ EXPORT_SYMBOL_GPL(serial8250_read_char);
> * (such as THRE) because the LSR value might come from an already consumed
> * character.
> */
> -unsigned char serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr)
> +u16 serial8250_rx_chars(struct uart_8250_port *up, u16 lsr)
> {
> struct uart_port *port = &up->port;
> int max_count = 256;
> @@ -1908,10 +1908,10 @@ static bool handle_rx_dma(struct uart_8250_port *up, unsigned int iir)
> */
> int serial8250_handle_irq(struct uart_port *port, unsigned int iir)
> {
> - unsigned char status;
> struct uart_8250_port *up = up_to_u8250p(port);
> bool skip_rx = false;
> unsigned long flags;
> + u16 status;
>
> if (iir & UART_IIR_NO_INT)
> return 0;
> @@ -1994,7 +1994,7 @@ static unsigned int serial8250_tx_empty(struct uart_port *port)
> {
> struct uart_8250_port *up = up_to_u8250p(port);
> unsigned long flags;
> - unsigned int lsr;
> + u16 lsr;
>
> serial8250_rpm_get(up);
>
> @@ -2117,8 +2117,8 @@ static void wait_for_xmitr(struct uart_8250_port *up, int bits)
> static int serial8250_get_poll_char(struct uart_port *port)
> {
> struct uart_8250_port *up = up_to_u8250p(port);
> - unsigned char lsr;
> int status;
> + u16 lsr;
>
> serial8250_rpm_get(up);
>
> @@ -2173,8 +2173,9 @@ int serial8250_do_startup(struct uart_port *port)
> {
> struct uart_8250_port *up = up_to_u8250p(port);
> unsigned long flags;
> - unsigned char lsr, iir;
> + unsigned char iir;
> int retval;
> + u16 lsr;
>
> if (!port->fifosize)
> port->fifosize = uart_config[port->type].fifo_size;
> diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h
> index ff84a3ed10ea..4565f25ba9a2 100644
> --- a/include/linux/serial_8250.h
> +++ b/include/linux/serial_8250.h
> @@ -119,7 +119,7 @@ struct uart_8250_port {
> * be immediately processed.
> */
> #define LSR_SAVE_FLAGS UART_LSR_BRK_ERROR_BITS
> - unsigned char lsr_saved_flags;
> + u16 lsr_saved_flags;
> #define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
> unsigned char msr_saved_flags;
>
> @@ -170,8 +170,8 @@ extern void serial8250_do_set_divisor(struct uart_port *port, unsigned int baud,
> unsigned int quot_frac);
> extern int fsl8250_handle_irq(struct uart_port *port);
> int serial8250_handle_irq(struct uart_port *port, unsigned int iir);
> -unsigned char serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr);
> -void serial8250_read_char(struct uart_8250_port *up, unsigned char lsr);
> +u16 serial8250_rx_chars(struct uart_8250_port *up, u16 lsr);
> +void serial8250_read_char(struct uart_8250_port *up, u16 lsr);
> void serial8250_tx_chars(struct uart_8250_port *up);
> unsigned int serial8250_modem_status(struct uart_8250_port *up);
> void serial8250_init_port(struct uart_8250_port *up);
> --
> 2.30.2
>

--
With Best Regards,
Andy Shevchenko

Next message: Will Deacon: "Re: [PATCH v5] memblock,arm64: Expand the static memblock memory table"
Previous message: Baolu Lu: "Re: [PATCH v9 10/11] iommu: Per-domain I/O page fault handling"
In reply to: Ilpo Järvinen: "[PATCH v9 1/6] serial: 8250: make saved LSR larger"
Next in thread: Ilpo Järvinen: "[PATCH v9 2/6] serial: 8250: create lsr_save_mask"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]