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authorMarek Vasut <marex@denx.de>2022-03-31 17:05:09 +0200
committerRobert Foss <robert.foss@linaro.org>2022-03-31 17:20:46 +0200
commit17a9c1aaa8485b7be0f20233bdc5bf0b4527f4a7 (patch)
tree2040d140ee4bee0bd9b209e9db3a55fa77caecaa /drivers
parent33f1036b785caeb5f0b7935ee771214cfd75b3f8 (diff)
downloadlinux-17a9c1aaa8485b7be0f20233bdc5bf0b4527f4a7.tar.bz2
drm: bridge: icn6211: Read and validate chip IDs before configuration
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. Acked-by: Maxime Ripard <maxime@cerno.tech> Signed-off-by: Marek Vasut <marex@denx.de> Cc: Jagan Teki <jagan@amarulasolutions.com> Cc: Maxime Ripard <maxime@cerno.tech> 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 Signed-off-by: Robert Foss <robert.foss@linaro.org> Link: https://patchwork.freedesktop.org/patch/msgid/20220331150509.9838-12-marex@denx.de
Diffstat (limited to 'drivers')
-rw-r--r--drivers/gpu/drm/bridge/chipone-icn6211.c24
1 files changed, 23 insertions, 1 deletions
diff --git a/drivers/gpu/drm/bridge/chipone-icn6211.c b/drivers/gpu/drm/bridge/chipone-icn6211.c
index f4dfb2297c71..a1bdb9be1927 100644
--- a/drivers/gpu/drm/bridge/chipone-icn6211.c
+++ b/drivers/gpu/drm/bridge/chipone-icn6211.c
@@ -151,6 +151,14 @@ static inline struct chipone *bridge_to_chipone(struct drm_bridge *bridge)
return container_of(bridge, struct chipone, bridge);
}
+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 int chipone_writeb(struct chipone *icn, u8 reg, u8 val)
{
if (icn->interface_i2c)
@@ -250,7 +258,21 @@ 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);