From: Huang Shijie Date: Tue, 4 Jun 2013 01:59:33 +0000 (+0800) Subject: serial: imx: enable the clocks only when the uart is used X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=15f04cd562a4aada50cca0e6f6b6f05e61447f4d;p=karo-tx-linux.git serial: imx: enable the clocks only when the uart is used Current code opens the clocks when the uart driver is probed. This will wastes some power if several uarts are enabled, but not really used. So close these clocks for uart, and enable the clocks only when the uart is used. Signed-off-by: Huang Shijie Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index a07e94f6a9fc..d290274e063c 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -700,6 +700,14 @@ static int imx_startup(struct uart_port *port) int retval; unsigned long flags, temp; + retval = clk_prepare_enable(sport->clk_per); + if (retval) + goto error_out1; + + retval = clk_prepare_enable(sport->clk_ipg); + if (retval) + goto error_out1; + imx_setup_ufcr(sport, 0); /* disable the DREN bit (Data Ready interrupt enable) before @@ -887,6 +895,9 @@ static void imx_shutdown(struct uart_port *port) writel(temp, sport->port.membase + UCR1); spin_unlock_irqrestore(&sport->port.lock, flags); + + clk_disable_unprepare(sport->clk_per); + clk_disable_unprepare(sport->clk_ipg); } static void @@ -1565,6 +1576,9 @@ static int serial_imx_probe(struct platform_device *pdev) goto deinit; platform_set_drvdata(pdev, sport); + clk_disable_unprepare(sport->clk_per); + clk_disable_unprepare(sport->clk_ipg); + return 0; deinit: if (pdata && pdata->exit) @@ -1586,9 +1600,6 @@ static int serial_imx_remove(struct platform_device *pdev) uart_remove_one_port(&imx_reg, &sport->port); - clk_disable_unprepare(sport->clk_per); - clk_disable_unprepare(sport->clk_ipg); - if (pdata && pdata->exit) pdata->exit(pdev);