diff options
| author | Martin Fuzzey <mfuzzey@parkeon.com> | 2016-01-05 16:53:31 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-02-06 22:53:43 -0800 |
| commit | 29add68d16474b7e8e3eadd94da4e909533b99d2 (patch) | |
| tree | dfecde2daf71d66a24c2f5e558e3e627d97e5e78 /drivers/tty | |
| parent | 07986580d0ad14433021b709c6c005e2757c5a68 (diff) | |
serial: imx: Fix suspend / resume.
When a non console i.MX UART is enabled in the device tree,
system suspend fails due to an unprepared clock:
[ 638.794563] PM: Syncing filesystems ... done.
[ 638.878902] Freezing user space processes ... (elapsed 0.002 seconds) done.
[ 638.888454] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
[ 638.996697] PM: suspend of devices complete after 97.200 msecs
[ 639.002611] PM: suspend devices took 0.100 seconds
[ 639.013020] PM: late suspend of devices complete after 2.288 msecs
[ 639.021486] ------------[ cut here ]------------
[ 639.026147] WARNING: CPU: 0 PID: 488 at drivers/clk/clk.c:732 clk_core_enable+0xc0/0x12c()
[ 639.034413] Modules linked in:
[ 639.037490] CPU: 0 PID: 488 Comm: system_server Tainted: G W 4.4.0-rc5-pknbsp-svn2214-atag-v4.4-rc5-121-gebfd9cb #1304
[ 639.049312] Hardware name: Freescale i.MX53 (Device Tree Support)
[ 639.055444] [<c0016d54>] (unwind_backtrace) from [<c00140f8>] (show_stack+0x20/0x24)
[ 639.063199] [<c00140f8>] (show_stack) from [<c02c99a0>] (dump_stack+0x20/0x28)
[ 639.070442] [<c02c99a0>] (dump_stack) from [<c0024ca8>] (warn_slowpath_common+0x88/0xc0)
[ 639.078541] [<c0024ca8>] (warn_slowpath_common) from [<c0024d0c>] (warn_slowpath_null+0x2c/0x34)
[ 639.087332] [<c0024d0c>] (warn_slowpath_null) from [<c05171e8>] (clk_core_enable+0xc0/0x12c)
[ 639.095777] [<c05171e8>] (clk_core_enable) from [<c05172f8>] (clk_enable+0x2c/0x40)
[ 639.103441] [<c05172f8>] (clk_enable) from [<c0349880>] (imx_serial_port_suspend_noirq+0x20/0xe0)
[ 639.112336] [<c0349880>] (imx_serial_port_suspend_noirq) from [<c03a26a0>] (dpm_run_callback+0x68/0x16c)
[ 639.121825] [<c03a26a0>] (dpm_run_callback) from [<c03a2898>] (__device_suspend_noirq+0xf4/0x22c)
[ 639.130705] [<c03a2898>] (__device_suspend_noirq) from [<c03a4b0c>] (dpm_suspend_noirq+0x148/0x30c)
[ 639.139764] [<c03a4b0c>] (dpm_suspend_noirq) from [<c00511d4>] (suspend_devices_and_enter+0x2e8/0x6a4)
[ 639.149078] [<c00511d4>] (suspend_devices_and_enter) from [<c00518a0>] (pm_suspend+0x310/0x4b8)
[ 639.157782] [<c00518a0>] (pm_suspend) from [<c00500ec>] (state_store+0x7c/0xcc)
[ 639.165099] [<c00500ec>] (state_store) from [<c02cb6dc>] (kobj_attr_store+0x1c/0x28)
[ 639.172858] [<c02cb6dc>] (kobj_attr_store) from [<c01633d4>] (sysfs_kf_write+0x54/0x58)
[ 639.180871] [<c01633d4>] (sysfs_kf_write) from [<c01629b4>] (kernfs_fop_write+0x100/0x1c8)
[ 639.189152] [<c01629b4>] (kernfs_fop_write) from [<c00fb8b8>] (__vfs_write+0x3c/0xe8)
[ 639.196991] [<c00fb8b8>] (__vfs_write) from [<c00fc810>] (vfs_write+0xa4/0x160)
[ 639.204307] [<c00fc810>] (vfs_write) from [<c00fcac4>] (SyS_write+0x4c/0x98)
[ 639.211363] [<c00fcac4>] (SyS_write) from [<c0010760>] (ret_fast_syscall+0x0/0x3c)
This does not happen for the common case of a single UART used as a console
(since imx_console_setup() already does a prepare)
Signed-off-by: Martin Fuzzey <mfuzzey@parkeon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/imx.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 9362f54c816c..231e7d5caf6c 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -2166,7 +2166,8 @@ static int imx_serial_port_suspend(struct device *dev) uart_suspend_port(&imx_reg, &sport->port); - return 0; + /* Needed to enable clock in suspend_noirq */ + return clk_prepare(sport->clk_ipg); } static int imx_serial_port_resume(struct device *dev) @@ -2179,6 +2180,8 @@ static int imx_serial_port_resume(struct device *dev) uart_resume_port(&imx_reg, &sport->port); + clk_unprepare(sport->clk_ipg); + return 0; } |