From 210417ce836aa3f0ededcc8f541f5e4a05d2e880 Mon Sep 17 00:00:00 2001 From: Shubhrajyoti Datta Date: Fri, 27 May 2016 15:05:19 +0530 Subject: [PATCH] tty: xuartps: disable clocks when not used Currently the clocks are enabled at probe and disabled at remove. Instead enable the clocks when used. Signed-off-by: Shubhrajyoti Datta Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/xilinx_uartps.c | 30 ++++++++++++++++++++++++------ 1 file changed, 24 insertions(+), 6 deletions(-) diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c index cd46e64c4255..9ca1a4d1b66a 100644 --- a/drivers/tty/serial/xilinx_uartps.c +++ b/drivers/tty/serial/xilinx_uartps.c @@ -976,6 +976,23 @@ static void cdns_uart_poll_put_char(struct uart_port *port, unsigned char c) } #endif +static void cdns_uart_pm(struct uart_port *port, unsigned int state, + unsigned int oldstate) +{ + struct cdns_uart *cdns_uart = port->private_data; + + switch (state) { + case UART_PM_STATE_OFF: + clk_disable(cdns_uart->uartclk); + clk_disable(cdns_uart->pclk); + break; + default: + clk_enable(cdns_uart->pclk); + clk_enable(cdns_uart->uartclk); + break; + } +} + static struct uart_ops cdns_uart_ops = { .set_mctrl = cdns_uart_set_mctrl, .get_mctrl = cdns_uart_get_mctrl, @@ -987,6 +1004,7 @@ static struct uart_ops cdns_uart_ops = { .set_termios = cdns_uart_set_termios, .startup = cdns_uart_startup, .shutdown = cdns_uart_shutdown, + .pm = cdns_uart_pm, .type = cdns_uart_type, .verify_port = cdns_uart_verify_port, .request_port = cdns_uart_request_port, @@ -1350,12 +1368,12 @@ static int cdns_uart_probe(struct platform_device *pdev) return PTR_ERR(cdns_uart_data->uartclk); } - rc = clk_prepare_enable(cdns_uart_data->pclk); + rc = clk_prepare(cdns_uart_data->pclk); if (rc) { dev_err(&pdev->dev, "Unable to enable pclk clock.\n"); return rc; } - rc = clk_prepare_enable(cdns_uart_data->uartclk); + rc = clk_prepare(cdns_uart_data->uartclk); if (rc) { dev_err(&pdev->dev, "Unable to enable device clock.\n"); goto err_out_clk_dis_pclk; @@ -1422,9 +1440,9 @@ err_out_notif_unreg: &cdns_uart_data->clk_rate_change_nb); #endif err_out_clk_disable: - clk_disable_unprepare(cdns_uart_data->uartclk); + clk_unprepare(cdns_uart_data->uartclk); err_out_clk_dis_pclk: - clk_disable_unprepare(cdns_uart_data->pclk); + clk_unprepare(cdns_uart_data->pclk); return rc; } @@ -1448,8 +1466,8 @@ static int cdns_uart_remove(struct platform_device *pdev) #endif rc = uart_remove_one_port(&cdns_uart_uart_driver, port); port->mapbase = 0; - clk_disable_unprepare(cdns_uart_data->uartclk); - clk_disable_unprepare(cdns_uart_data->pclk); + clk_unprepare(cdns_uart_data->uartclk); + clk_unprepare(cdns_uart_data->pclk); return rc; } -- 2.20.1