All of lore.kernel.org
 help / color / mirror / Atom feed
From: Jacopo Mondi <jacopo+renesas@jmondi.org>
To: Hans Verkuil <hverkuil-cisco@xs4all.nl>,
	kieran.bingham+renesas@ideasonboard.com,
	laurent.pinchart+renesas@ideasonboard.com,
	niklas.soderlund+renesas@ragnatech.se, geert@linux-m68k.org
Cc: Jacopo Mondi <jacopo+renesas@jmondi.org>,
	Mauro Carvalho Chehab <mchehab@kernel.org>,
	linux-media@vger.kernel.org, linux-renesas-soc@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Subject: [PATCH v5 09/15] media: i2c: rdacm21: Fix OV10640 powerup
Date: Wed, 16 Jun 2021 14:46:10 +0200	[thread overview]
Message-ID: <20210616124616.49249-10-jacopo+renesas@jmondi.org> (raw)
In-Reply-To: <20210616124616.49249-1-jacopo+renesas@jmondi.org>

The OV10640 image sensor powerdown signal is controlled by the first
line of the OV490 GPIO pad #1, but the pad #0 identifier
OV490_GPIO_OUTPUT_VALUE0 was erroneously used. As a result the image
sensor powerdown signal was never asserted but was left floating and
kept high by an internal pull-up resistor, causing sporadic failures
during the image sensor startup phase.

Fix this by using the correct GPIO pad identifier and wait the mandatory
1.5 millisecond delay after the powerup lane is asserted. The reset
delay is not characterized in the chip manual if not as "255 XVCLK +
initialization". Wait for at least 3 milliseconds to guarantee the SCCB
bus is available.

While at it also fix the reset sequence, as the reset line was released
before the powerdown one, and the line was not cycled.

This commit fixes a sporadic start-up error triggered by a failure to
read the OV10640 chip ID:
rdacm21 8-0054: OV10640 ID mismatch: (0x01)

Fixes: a59f853b3b4b ("media: i2c: Add driver for RDACM21 camera module")
Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
 drivers/media/i2c/rdacm21.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/media/i2c/rdacm21.c b/drivers/media/i2c/rdacm21.c
index 6be8ce130e78..7c0a4a84340a 100644
--- a/drivers/media/i2c/rdacm21.c
+++ b/drivers/media/i2c/rdacm21.c
@@ -333,13 +333,19 @@ static int ov10640_initialize(struct rdacm21_device *dev)
 {
 	u8 val;
 
-	/* Power-up OV10640 by setting RESETB and PWDNB pins high. */
+	/* Enable GPIO0#0 (reset) and GPIO1#0 (pwdn) as output lines. */
 	ov490_write_reg(dev, OV490_GPIO_SEL0, OV490_GPIO0);
 	ov490_write_reg(dev, OV490_GPIO_SEL1, OV490_SPWDN0);
 	ov490_write_reg(dev, OV490_GPIO_DIRECTION0, OV490_GPIO0);
 	ov490_write_reg(dev, OV490_GPIO_DIRECTION1, OV490_SPWDN0);
+
+	/* Power up OV10640 and then reset it. */
+	ov490_write_reg(dev, OV490_GPIO_OUTPUT_VALUE1, OV490_SPWDN0);
+	usleep_range(1500, 3000);
+
+	ov490_write_reg(dev, OV490_GPIO_OUTPUT_VALUE0, 0x00);
+	usleep_range(1500, 3000);
 	ov490_write_reg(dev, OV490_GPIO_OUTPUT_VALUE0, OV490_GPIO0);
-	ov490_write_reg(dev, OV490_GPIO_OUTPUT_VALUE0, OV490_SPWDN0);
 	usleep_range(3000, 5000);
 
 	/* Read OV10640 ID to test communications. */
-- 
2.31.1


  parent reply	other threads:[~2021-06-16 12:46 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-16 12:46 [PATCH v5 00/15] media: gmsl: Reliability improvements Jacopo Mondi
2021-06-16 12:46 ` [PATCH v5 01/15] media: i2c: max9286: Adjust parameters indent Jacopo Mondi
2021-06-16 12:46 ` [PATCH v5 02/15] media: i2c: max9286: Rename reverse_channel_mv Jacopo Mondi
2021-06-16 12:46 ` [PATCH v5 03/15] media: i2c: max9286: Cache channel amplitude Jacopo Mondi
2021-06-16 12:46 ` [PATCH v5 04/15] media: i2c: max9286: Define high " Jacopo Mondi
2021-06-16 12:46 ` [PATCH v5 05/15] media: i2c: max9286: Rework comments in .bound() Jacopo Mondi
2021-06-16 12:46 ` [PATCH v5 06/15] media: i2c: max9271: Check max9271_write() return Jacopo Mondi
2021-06-16 12:46 ` [PATCH v5 07/15] media: i2c: max9271: Introduce wake_up() function Jacopo Mondi
2021-06-16 12:46 ` [PATCH v5 08/15] media: i2c: rdacm21: Add delay after OV490 reset Jacopo Mondi
2021-06-16 12:46 ` Jacopo Mondi [this message]
2021-06-16 12:46 ` [PATCH v5 10/15] media: i2c: rdacm21: Power up OV10640 before OV490 Jacopo Mondi
2021-06-16 23:47   ` Kieran Bingham
2021-06-16 12:46 ` [PATCH v5 11/15] media: i2c: rdacm20: Enable noise immunity Jacopo Mondi
2021-06-16 12:46 ` [PATCH v5 12/15] media: i2c: rdacm20: Embed 'serializer' field Jacopo Mondi
2021-06-17  0:14   ` Laurent Pinchart
2021-06-17  6:18     ` Hans Verkuil
2021-06-17  7:42       ` Jacopo Mondi
2021-06-17  8:12         ` Hans Verkuil
2021-06-17  8:20           ` Jacopo Mondi
2021-06-16 12:46 ` [PATCH v5 13/15] media: i2c: rdacm20: Report camera module name Jacopo Mondi
2021-06-16 12:46 ` [PATCH v5 14/15] media: i2c: rdacm20: Check return values Jacopo Mondi
2021-06-16 12:46 ` [PATCH v5 15/15] media: i2c: rdacm20: Re-work ov10635 reset Jacopo Mondi

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=20210616124616.49249-10-jacopo+renesas@jmondi.org \
    --to=jacopo+renesas@jmondi.org \
    --cc=geert@linux-m68k.org \
    --cc=hverkuil-cisco@xs4all.nl \
    --cc=kieran.bingham+renesas@ideasonboard.com \
    --cc=laurent.pinchart+renesas@ideasonboard.com \
    --cc=laurent.pinchart@ideasonboard.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-media@vger.kernel.org \
    --cc=linux-renesas-soc@vger.kernel.org \
    --cc=mchehab@kernel.org \
    --cc=niklas.soderlund+renesas@ragnatech.se \
    --subject='Re: [PATCH v5 09/15] media: i2c: rdacm21: Fix OV10640 powerup' \
    /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

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.