All of lore.kernel.org
 help / color / mirror / Atom feed
From: Marek Vasut <marex@denx.de>
To: dri-devel@lists.freedesktop.org
Cc: Marek Vasut <marex@denx.de>,
	Thomas Zimmermann <tzimmermann@suse.de>,
	Sam Ravnborg <sam@ravnborg.org>,
	Jagan Teki <jagan@amarulasolutions.com>,
	Robert Foss <robert.foss@linaro.org>
Subject: [PATCH 14/14] drm: bridge: icn6211: Read and validate chip IDs before configuration
Date: Fri, 14 Jan 2022 04:48:38 +0100	[thread overview]
Message-ID: <20220114034838.546267-14-marex@denx.de> (raw)
In-Reply-To: <20220114034838.546267-1-marex@denx.de>

Read out the Vendor/Chip/Version ID registers from the chip before
performing any configuration, and validate that the registers have
correct values. This is mostly a simple test whether DSI register
access does work, since that tends to be broken on various bridges.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Jagan Teki <jagan@amarulasolutions.com>
Cc: Robert Foss <robert.foss@linaro.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
To: dri-devel@lists.freedesktop.org
---
 drivers/gpu/drm/bridge/chipone-icn6211.c | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/chipone-icn6211.c b/drivers/gpu/drm/bridge/chipone-icn6211.c
index 3023edb6f31b5..85cba739afd9c 100644
--- a/drivers/gpu/drm/bridge/chipone-icn6211.c
+++ b/drivers/gpu/drm/bridge/chipone-icn6211.c
@@ -176,6 +176,14 @@ bridge_to_mode(struct drm_bridge *bridge, struct drm_atomic_state *state)
 	return &crtc_state->adjusted_mode;
 }
 
+static void chipone_readb(struct chipone *icn, u8 reg, u8 *val)
+{
+	if (icn->interface_i2c)
+		*val = i2c_smbus_read_byte_data(icn->client, reg);
+	else
+		mipi_dsi_generic_read(icn->dsi, (u8[]){reg, 1}, 2, val, 1);
+}
+
 static void chipone_writeb(struct chipone *icn, u8 reg, u8 val)
 {
 	if (icn->interface_i2c)
@@ -274,7 +282,21 @@ static void chipone_atomic_enable(struct drm_bridge *bridge,
 	const struct drm_bridge_state *bridge_state;
 	u16 hfp, hbp, hsync;
 	u32 bus_flags;
-	u8 pol;
+	u8 pol, id[4];
+
+	chipone_readb(icn, VENDOR_ID, id);
+	chipone_readb(icn, DEVICE_ID_H, id + 1);
+	chipone_readb(icn, DEVICE_ID_L, id + 2);
+	chipone_readb(icn, VERSION_ID, id + 3);
+
+	dev_dbg(icn->dev,
+		"Chip IDs: Vendor=0x%02x Device=0x%02x:0x%02x Version=0x%02x\n",
+		id[0], id[1], id[2], id[3]);
+
+	if (id[0] != 0xc1 || id[1] != 0x62 || id[2] != 0x11) {
+		dev_dbg(icn->dev, "Invalid Chip IDs, aborting configuration\n");
+		return;
+	}
 
 	/* Get the DPI flags from the bridge state. */
 	bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
-- 
2.34.1


  parent reply	other threads:[~2022-01-14  3:49 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-01-14  3:48 [PATCH 01/14] drm: bridge: icn6211: Fix register layout Marek Vasut
2022-01-14  3:48 ` [PATCH 02/14] drm: bridge: icn6211: Fix HFP_HSW_HBP_HI and HFP_MIN handling Marek Vasut
2022-01-14  3:48 ` [PATCH 03/14] drm: bridge: icn6211: Switch to atomic operations Marek Vasut
2022-01-14  3:48 ` [PATCH 04/14] drm: bridge: icn6211: Implement atomic_get_input_bus_fmts Marek Vasut
2022-01-14  3:48 ` [PATCH 05/14] drm: bridge: icn6211: Retrieve the display mode from the state Marek Vasut
2022-02-03 12:09   ` Maxime Ripard
2022-02-16 20:13     ` Marek Vasut
2022-01-14  3:48 ` [PATCH 06/14] drm: bridge: icn6211: Add HS/VS/DE polarity handling Marek Vasut
2022-01-14  3:48 ` [PATCH 07/14] drm: bridge: icn6211: Add DSI lane count DT property parsing Marek Vasut
2022-02-03 12:13   ` Maxime Ripard
2022-02-16 20:24     ` Marek Vasut
2022-01-14  3:48 ` [PATCH 08/14] drm: bridge: icn6211: Add generic DSI-to-DPI PLL configuration Marek Vasut
2022-01-14  3:48 ` [PATCH 09/14] drm: bridge: icn6211: Use DSI burst mode without EoT and with LP command mode Marek Vasut
2022-01-14  3:48 ` [PATCH 10/14] drm: bridge: icn6211: Disable DPI color swap Marek Vasut
2022-01-14  3:48 ` [PATCH 11/14] drm: bridge: icn6211: Set SYS_CTRL_1 to value used in examples Marek Vasut
2022-01-14  3:48 ` [PATCH 12/14] drm: bridge: icn6211: Add I2C configuration support Marek Vasut
2022-01-14 10:24   ` kernel test robot
2022-01-14 10:24     ` kernel test robot
2022-02-03 12:17   ` Maxime Ripard
2022-01-14  3:48 ` [PATCH 13/14] drm: bridge: icn6211: Rename ICN6211_DSI to chipone_writeb Marek Vasut
2022-01-14  3:48 ` Marek Vasut [this message]
2022-01-14  8:16 ` [PATCH 01/14] drm: bridge: icn6211: Fix register layout Jagan Teki
2022-01-14 14:33   ` Marek Vasut

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=20220114034838.546267-14-marex@denx.de \
    --to=marex@denx.de \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=jagan@amarulasolutions.com \
    --cc=robert.foss@linaro.org \
    --cc=sam@ravnborg.org \
    --cc=tzimmermann@suse.de \
    /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 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.