linux-kernel - [PATCH v4 1/6] media: i2c: ov5640: Remain in power down for DVP mode unless streaming

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20200904201835.5958-2-prabhakar.mahadev-lad.rj@bp.renesas.com>
Date:   Fri,  4 Sep 2020 21:18:30 +0100
From:   Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>
To:     Jacopo Mondi <jacopo+renesas@...ndi.org>,
        Sakari Ailus <sakari.ailus@...ux.intel.com>,
        Laurent Pinchart <laurent.pinchart@...asonboard.com>,
        Steve Longerbeam <slongerbeam@...il.com>,
        Paul <paul.kocialkowski@...tlin.com>,
        Hugues Fruchet <hugues.fruchet@...com>
Cc:     linux-media@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-renesas-soc@...r.kernel.org,
        Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>,
        Biju Das <biju.das.jz@...renesas.com>,
        Prabhakar <prabhakar.csengg@...il.com>,
        Mauro Carvalho Chehab <mchehab@...nel.org>
Subject: [PATCH v4 1/6] media: i2c: ov5640: Remain in power down for DVP mode unless streaming

Keep the sensor in software power down mode and wake up only in
ov5640_set_stream_dvp() callback.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>
Reviewed-by: Biju Das <biju.das.jz@...renesas.com>
Tested-by: Jacopo Mondi <jacopo@...ndi.org>
---
 drivers/media/i2c/ov5640.c | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c
index 2fe4a7ac0592..880fde73a030 100644
--- a/drivers/media/i2c/ov5640.c
+++ b/drivers/media/i2c/ov5640.c
@@ -34,6 +34,8 @@
 #define OV5640_REG_SYS_RESET02		0x3002
 #define OV5640_REG_SYS_CLOCK_ENABLE02	0x3006
 #define OV5640_REG_SYS_CTRL0		0x3008
+#define OV5640_REG_SYS_CTRL0_SW_PWDN	0x42
+#define OV5640_REG_SYS_CTRL0_SW_PWUP	0x02
 #define OV5640_REG_CHIP_ID		0x300a
 #define OV5640_REG_IO_MIPI_CTRL00	0x300e
 #define OV5640_REG_PAD_OUTPUT_ENABLE01	0x3017
@@ -1120,6 +1122,12 @@ static int ov5640_load_regs(struct ov5640_dev *sensor,
 		val = regs->val;
 		mask = regs->mask;
 
+		/* remain in power down mode for DVP */
+		if (regs->reg_addr == OV5640_REG_SYS_CTRL0 &&
+		    val == OV5640_REG_SYS_CTRL0_SW_PWUP &&
+		    sensor->ep.bus_type != V4L2_MBUS_CSI2_DPHY)
+			continue;
+
 		if (mask)
 			ret = ov5640_mod_reg(sensor, reg_addr, mask, val);
 		else
@@ -1297,9 +1305,14 @@ static int ov5640_set_stream_dvp(struct ov5640_dev *sensor, bool on)
 	 * PAD OUTPUT ENABLE 02
 	 * - [7:2]:	D[5:0] output enable
 	 */
-	return ov5640_write_reg(sensor,
-				OV5640_REG_PAD_OUTPUT_ENABLE02,
-				on ? 0xfc : 0);
+	ret = ov5640_write_reg(sensor, OV5640_REG_PAD_OUTPUT_ENABLE02,
+			       on ? 0xfc : 0);
+	if (ret)
+		return ret;
+
+	return ov5640_write_reg(sensor, OV5640_REG_SYS_CTRL0, on ?
+				OV5640_REG_SYS_CTRL0_SW_PWUP :
+				OV5640_REG_SYS_CTRL0_SW_PWDN);
 }
 
 static int ov5640_set_stream_mipi(struct ov5640_dev *sensor, bool on)
-- 
2.17.1