Re: [PATCH v2 17/25] tty: serial: samsung_tty: Separate S3C64XX ops structure
From: Krzysztof Kozlowski <krzk@kernel.org>
Date: 2021-02-15 18:08:02
Also in:
linux-arm-kernel, lkml
On Mon, Feb 15, 2021 at 09:17:05PM +0900, Hector Martin wrote:
quoted hunk ↗ jump to hunk
Instead of patching a single global ops structure depending on the port type, use a separate s3c64xx_serial_ops for the S3C64XX type. This allows us to mark the structures as const. Also split out s3c64xx_serial_shutdown into a separate function now that we have a separate ops structure; this avoids excessive branching control flow and mirrors s3c64xx_serial_startup. tx_claimed and rx_claimed are only used in the S3C24XX functions. Signed-off-by: Hector Martin <redacted> --- drivers/tty/serial/samsung_tty.c | 69 ++++++++++++++++++++++++-------- 1 file changed, 53 insertions(+), 16 deletions(-)diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c index 8ae3e03fbd8c..6b661f3ec1ae 100644 --- a/drivers/tty/serial/samsung_tty.c +++ b/drivers/tty/serial/samsung_tty.c@@ -1098,27 +1098,36 @@ static void s3c24xx_serial_shutdown(struct uart_port *port) struct s3c24xx_uart_port *ourport = to_ourport(port); if (ourport->tx_claimed) { - if (!s3c24xx_serial_has_interrupt_mask(port)) - free_irq(ourport->tx_irq, ourport); + free_irq(ourport->tx_irq, ourport); ourport->tx_enabled = 0; ourport->tx_claimed = 0; ourport->tx_mode = 0; } if (ourport->rx_claimed) { - if (!s3c24xx_serial_has_interrupt_mask(port)) - free_irq(ourport->rx_irq, ourport); + free_irq(ourport->rx_irq, ourport); ourport->rx_claimed = 0; ourport->rx_enabled = 0; } - /* Clear pending interrupts and mask all interrupts */ - if (s3c24xx_serial_has_interrupt_mask(port)) { - free_irq(port->irq, ourport); + if (ourport->dma) + s3c24xx_serial_release_dma(ourport); - wr_regl(port, S3C64XX_UINTP, 0xf); - wr_regl(port, S3C64XX_UINTM, 0xf); - } + ourport->tx_in_progress = 0; +} + +static void s3c64xx_serial_shutdown(struct uart_port *port) +{ + struct s3c24xx_uart_port *ourport = to_ourport(port); + + free_irq(port->irq, ourport); + + wr_regl(port, S3C64XX_UINTP, 0xf); + wr_regl(port, S3C64XX_UINTM, 0xf); + + ourport->tx_enabled = 0; + ourport->tx_mode = 0; + ourport->rx_enabled = 0;
For S3C64xx type this is not equivalent: the assignments were happening before free_irq() and wr_regl(). Honestly I don't know whether it matters (except some barriers coming from these functions) but please do not change the order of code in this patch. If needed, the re-ordering should be a patch on its own. With explanation why.
quoted hunk ↗ jump to hunk
if (ourport->dma) s3c24xx_serial_release_dma(ourport);@@ -1193,9 +1202,7 @@ static int s3c64xx_serial_startup(struct uart_port *port) /* For compatibility with s3c24xx Soc's */ ourport->rx_enabled = 1; - ourport->rx_claimed = 1; ourport->tx_enabled = 0; - ourport->tx_claimed = 1; spin_lock_irqsave(&port->lock, flags);@@ -1631,6 +1638,29 @@ static struct uart_ops s3c24xx_serial_ops = { #endif }; +static const struct uart_ops s3c64xx_serial_ops = { + .pm = s3c24xx_serial_pm, + .tx_empty = s3c24xx_serial_tx_empty, + .get_mctrl = s3c24xx_serial_get_mctrl, + .set_mctrl = s3c24xx_serial_set_mctrl, + .stop_tx = s3c24xx_serial_stop_tx, + .start_tx = s3c24xx_serial_start_tx, + .stop_rx = s3c24xx_serial_stop_rx, + .break_ctl = s3c24xx_serial_break_ctl, + .startup = s3c64xx_serial_startup, + .shutdown = s3c64xx_serial_shutdown, + .set_termios = s3c24xx_serial_set_termios, + .type = s3c24xx_serial_type, + .release_port = s3c24xx_serial_release_port, + .request_port = s3c24xx_serial_request_port, + .config_port = s3c24xx_serial_config_port, + .verify_port = s3c24xx_serial_verify_port, +#if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL) + .poll_get_char = s3c24xx_serial_get_poll_char, + .poll_put_char = s3c24xx_serial_put_poll_char, +#endif +}; +
Make the s3c24xx_serial_ops const as well. Best regards, Krzysztof