From 9e7b399d6528eac33a6fbfceb2b92af209c3454d Mon Sep 17 00:00:00 2001 From: Eduardo Valentin Date: Tue, 11 Aug 2015 10:21:20 -0700 Subject: [PATCH] serial: imx: remove unbalanced clk_prepare The current code attempts to prepare clk_per and clk_ipg before using the device. However, the result is an extra prepare call on each clock. Here is the output of uart clocks (only uart enabled and used as console): $ grep uart /sys/kernel/debug/clk/clk_summary uart_serial 1 2 80000000 0 0 uart 1 2 66000000 0 0 This patch balances the calls of prepares. The result is: $ grep uart /sys/kernel/debug/clk/clk_summary uart_serial 1 1 80000000 0 0 uart 1 1 66000000 0 0 Cc: Fabio Estevam Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: linux-serial@vger.kernel.org Cc: linux-pm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Eduardo Valentin Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/imx.c | 20 ++++++-------------- 1 file changed, 6 insertions(+), 14 deletions(-) diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 9a248eb11308..b27c23256a51 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -1630,12 +1630,12 @@ imx_console_write(struct console *co, const char *s, unsigned int count) int locked = 1; int retval; - retval = clk_enable(sport->clk_per); + retval = clk_prepare_enable(sport->clk_per); if (retval) return; - retval = clk_enable(sport->clk_ipg); + retval = clk_prepare_enable(sport->clk_ipg); if (retval) { - clk_disable(sport->clk_per); + clk_disable_unprepare(sport->clk_per); return; } @@ -1674,8 +1674,8 @@ imx_console_write(struct console *co, const char *s, unsigned int count) if (locked) spin_unlock_irqrestore(&sport->port.lock, flags); - clk_disable(sport->clk_ipg); - clk_disable(sport->clk_per); + clk_disable_unprepare(sport->clk_ipg); + clk_disable_unprepare(sport->clk_per); } /* @@ -1776,15 +1776,7 @@ imx_console_setup(struct console *co, char *options) retval = uart_set_options(&sport->port, co, baud, parity, bits, flow); - clk_disable(sport->clk_ipg); - if (retval) { - clk_unprepare(sport->clk_ipg); - goto error_console; - } - - retval = clk_prepare(sport->clk_per); - if (retval) - clk_disable_unprepare(sport->clk_ipg); + clk_disable_unprepare(sport->clk_ipg); error_console: return retval; -- GitLab