From 046c217c65a7670b4ee1aecdb9854284e32b2d6c Mon Sep 17 00:00:00 2001 From: Thomas Abraham Date: Mon, 24 Oct 2011 11:47:40 +0200 Subject: ARM: S3C2440: move handling of fclk/n clock to platform code s3c2440 uses fclk/n (fclk divided by n) clock as one of the possible clocks used to generate the baud rate clock. The divider 'n' in this case can be logically represented outside of the uart controller. This patch creates a new clock by name "fclk_n" for s3c2440 based platforms to represent the fclk/n clock in the platform code. This clock provides a get_rate callback that checks the UCON0/1/2 registers to determine the clock rate. The samsung uart driver would receive the "fclk_n" clock name as one of the possible baud rate clock options and the driver need not determine clock rate of fclk/n. Cc: Ben Dooks Cc: Vasily Khoruzhick Signed-off-by: Thomas Abraham Signed-off-by: Kukjin Kim --- drivers/tty/serial/s3c2440.c | 33 +++------------------------------ drivers/tty/serial/samsung.c | 21 --------------------- 2 files changed, 3 insertions(+), 51 deletions(-) (limited to 'drivers/tty') diff --git a/drivers/tty/serial/s3c2440.c b/drivers/tty/serial/s3c2440.c index 1d0c324b813..4498828630f 100644 --- a/drivers/tty/serial/s3c2440.c +++ b/drivers/tty/serial/s3c2440.c @@ -39,7 +39,7 @@ static int s3c2440_serial_setsource(struct uart_port *port, ucon |= S3C2440_UCON_UCLK; else if (strcmp(clk->name, "pclk") == 0) ucon |= S3C2440_UCON_PCLK; - else if (strcmp(clk->name, "fclk") == 0) + else if (strcmp(clk->name, "fclk_n") == 0) ucon |= S3C2440_UCON_FCLK; else { printk(KERN_ERR "unknown clock source %s\n", clk->name); @@ -55,7 +55,6 @@ static int s3c2440_serial_getsource(struct uart_port *port, struct s3c24xx_uart_clksrc *clk) { unsigned long ucon = rd_regl(port, S3C2410_UCON); - unsigned long ucon0, ucon1, ucon2; switch (ucon & S3C2440_UCON_CLKMASK) { case S3C2440_UCON_UCLK: @@ -70,34 +69,8 @@ static int s3c2440_serial_getsource(struct uart_port *port, break; case S3C2440_UCON_FCLK: - /* the fun of calculating the uart divisors on - * the s3c2440 */ - - ucon0 = __raw_readl(S3C24XX_VA_UART0 + S3C2410_UCON); - ucon1 = __raw_readl(S3C24XX_VA_UART1 + S3C2410_UCON); - ucon2 = __raw_readl(S3C24XX_VA_UART2 + S3C2410_UCON); - - printk("ucons: %08lx, %08lx, %08lx\n", ucon0, ucon1, ucon2); - - ucon0 &= S3C2440_UCON0_DIVMASK; - ucon1 &= S3C2440_UCON1_DIVMASK; - ucon2 &= S3C2440_UCON2_DIVMASK; - - if (ucon0 != 0) { - clk->divisor = ucon0 >> S3C2440_UCON_DIVSHIFT; - clk->divisor += 6; - } else if (ucon1 != 0) { - clk->divisor = ucon1 >> S3C2440_UCON_DIVSHIFT; - clk->divisor += 21; - } else if (ucon2 != 0) { - clk->divisor = ucon2 >> S3C2440_UCON_DIVSHIFT; - clk->divisor += 36; - } else { - /* manual calims 44, seems to be 9 */ - clk->divisor = 9; - } - - clk->name = "fclk"; + clk->divisor = 1; + clk->name = "fclk_n"; break; } diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c index 51cfb9f1166..fc242b2fd36 100644 --- a/drivers/tty/serial/samsung.c +++ b/drivers/tty/serial/samsung.c @@ -649,27 +649,6 @@ static unsigned int s3c24xx_serial_getclk(struct uart_port *port, if (cfg->clocks_size == 0) clkp = &tmp_clksrc; - /* check to see if we're sourcing fclk, and if so we're - * going to have to update the clock source - */ - - if (strcmp(clkp->name, "fclk") == 0) { - struct s3c24xx_uart_clksrc src; - - s3c24xx_serial_getsource(port, &src); - - /* check that the port already using fclk, and if - * not, then re-select fclk - */ - - if (strcmp(src.name, clkp->name) == 0) { - s3c24xx_serial_setsource(port, clkp); - s3c24xx_serial_getsource(port, &src); - } - - clkp->divisor = src.divisor; - } - s3c24xx_serial_calcbaud(res, port, clkp, baud); best = res; resptr = best + 1; -- cgit v1.2.3-18-g5258