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authorLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>2017-01-17 11:29:03 +0300
committerArchit Taneja <architt@codeaurora.org>2017-01-18 06:59:34 +0300
commit0527e12e8264ae96b1fcc550b4a9e5940f4ffc30 (patch)
tree3bdc49da007f85bba3f5f2566719e87ddcd9a00b
parentf4104e8fe12c173fbba5e7e30b846e09eeb5bfbd (diff)
downloadlinux-0527e12e8264ae96b1fcc550b4a9e5940f4ffc30.tar.xz
drm: bridge: dw-hdmi: Reject invalid product IDs
The DWC HDMI TX can be recognized by the two product identification registers. If the registers don't read as expect the IP will be very different than what the driver has been designed for, or will be misconfigured in a way that makes it non-operational (invalid memory address, incorrect clocks, ...). We should reject this situation with an error. While this isn't critical for proper operation with supported IPs at the moment, the driver will soon gain automatic device-specific handling based on runtime device identification. This change makes it easier to implement that without having to default to a random guess in case the device can't be identified. While at it print a readable version number in the device identification message instead of raw register values. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Reviewed-by: Jose Abreu <joabreu@synopsys.com> Signed-off-by: Archit Taneja <architt@codeaurora.org> Link: http://patchwork.freedesktop.org/patch/msgid/20170117082910.27023-14-laurent.pinchart+renesas@ideasonboard.com
-rw-r--r--drivers/gpu/drm/bridge/dw-hdmi.c25
-rw-r--r--drivers/gpu/drm/bridge/dw-hdmi.h8
2 files changed, 27 insertions, 6 deletions
diff --git a/drivers/gpu/drm/bridge/dw-hdmi.c b/drivers/gpu/drm/bridge/dw-hdmi.c
index 06c252f560ad..1809247745b8 100644
--- a/drivers/gpu/drm/bridge/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/dw-hdmi.c
@@ -1832,6 +1832,9 @@ __dw_hdmi_probe(struct platform_device *pdev,
int irq;
int ret;
u32 val = 1;
+ u16 version;
+ u8 prod_id0;
+ u8 prod_id1;
u8 config0;
u8 config1;
@@ -1914,12 +1917,22 @@ __dw_hdmi_probe(struct platform_device *pdev,
}
/* Product and revision IDs */
- dev_info(dev,
- "Detected HDMI controller 0x%x:0x%x:0x%x:0x%x\n",
- hdmi_readb(hdmi, HDMI_DESIGN_ID),
- hdmi_readb(hdmi, HDMI_REVISION_ID),
- hdmi_readb(hdmi, HDMI_PRODUCT_ID0),
- hdmi_readb(hdmi, HDMI_PRODUCT_ID1));
+ version = (hdmi_readb(hdmi, HDMI_DESIGN_ID) << 8)
+ | (hdmi_readb(hdmi, HDMI_REVISION_ID) << 0);
+ prod_id0 = hdmi_readb(hdmi, HDMI_PRODUCT_ID0);
+ prod_id1 = hdmi_readb(hdmi, HDMI_PRODUCT_ID1);
+
+ if (prod_id0 != HDMI_PRODUCT_ID0_HDMI_TX ||
+ (prod_id1 & ~HDMI_PRODUCT_ID1_HDCP) != HDMI_PRODUCT_ID1_HDMI_TX) {
+ dev_err(dev, "Unsupported HDMI controller (%04x:%02x:%02x)\n",
+ version, prod_id0, prod_id1);
+ ret = -ENODEV;
+ goto err_iahb;
+ }
+
+ dev_info(dev, "Detected HDMI TX controller v%x.%03x %s HDCP\n",
+ version >> 12, version & 0xfff,
+ prod_id1 & HDMI_PRODUCT_ID1_HDCP ? "with" : "without");
initialize_hdmi_ih_mutes(hdmi);
diff --git a/drivers/gpu/drm/bridge/dw-hdmi.h b/drivers/gpu/drm/bridge/dw-hdmi.h
index 08235aef2fa3..91d7fabbd6e5 100644
--- a/drivers/gpu/drm/bridge/dw-hdmi.h
+++ b/drivers/gpu/drm/bridge/dw-hdmi.h
@@ -545,6 +545,14 @@
#define HDMI_I2CM_FS_SCL_LCNT_0_ADDR 0x7E12
enum {
+/* PRODUCT_ID0 field values */
+ HDMI_PRODUCT_ID0_HDMI_TX = 0xa0,
+
+/* PRODUCT_ID1 field values */
+ HDMI_PRODUCT_ID1_HDCP = 0xc0,
+ HDMI_PRODUCT_ID1_HDMI_RX = 0x02,
+ HDMI_PRODUCT_ID1_HDMI_TX = 0x01,
+
/* CONFIG0_ID field values */
HDMI_CONFIG0_I2S = 0x10,