linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: khilman@deeprootsystems.com (Kevin Hilman)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v2] ARM: OMAP2: UART: fix console UART mismatched runtime PM status
Date: Fri, 19 Oct 2012 15:24:30 -0700	[thread overview]
Message-ID: <1350685470-3634-1-git-send-email-khilman@deeprootsystems.com> (raw)

From: Kevin Hilman <khilman@ti.com>

The runtime PM framework assumes that the hardware state of devices
when initialized is disabled.  For all omap_devices, we idle/disable
device by default.  However, the console uart uses a "no idle" option
during omap_device init in order to allow earlyprintk usage to work
seamlessly during boot.

Because the hardware is left partially enabled after init (whatever
the bootloader settings were), the omap_device should later be fully
initialized (including mux) and the runtime PM framework should be
told that the device is active, and not disabled so that the hardware
state is in sync with runtime PM state.

To fix, after the device has been created/registered, call
omap_device_enable() to finialize init and use pm_runtime_set_active()
to tell the runtime PM core the device is enabled.

Tested on 2420/n810, 3530/Overo, 3530/Beagle, 3730/OveroSTORM,
3730/Beagle-xM, 4460/PandaES.

Suggested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Sourav Poddar <sourav.poddar@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
---
Applies to v3.7-rc1.
v2: call omap_device_enable() only after oh->mux has been initialized
    otherwise, IO ring wakeups not properly enabled.

 arch/arm/mach-omap2/serial.c |    5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
index 0405c81..a507cd6 100644
--- a/arch/arm/mach-omap2/serial.c
+++ b/arch/arm/mach-omap2/serial.c
@@ -329,6 +329,11 @@ void __init omap_serial_init_port(struct omap_board_data *bdata,
 
 	oh->mux = omap_hwmod_mux_init(bdata->pads, bdata->pads_cnt);
 
+	if (console_uart_id == bdata->id) {
+		omap_device_enable(pdev);
+		pm_runtime_set_active(&pdev->dev);
+	}
+
 	oh->dev_attr = uart;
 
 	if (((cpu_is_omap34xx() || cpu_is_omap44xx()) && bdata->pads)
-- 
1.7.9.2

             reply	other threads:[~2012-10-19 22:24 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-10-19 22:24 Kevin Hilman [this message]
2012-10-22 12:13 ` [PATCH v2] ARM: OMAP2: UART: fix console UART mismatched runtime PM status Sourav

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1350685470-3634-1-git-send-email-khilman@deeprootsystems.com \
    --to=khilman@deeprootsystems.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).