<div dir="auto"><div><br><br><div class="gmail_quote"><div dir="ltr">On Wed, Aug 8, 2018, 5:53 PM Sean Paul <<a href="mailto:seanpaul@chromium.org">seanpaul@chromium.org</a>> wrote:<br></div><div dir="ltr"><br></div><div dir="ltr">Just realized I put drm/panel in the subject, should be drm/bridge. </div><div dir="ltr"><br></div><div dir="ltr">Sean</div><div dir="ltr"><br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">This was hand-rolled in the first version, and will surely be useful as<br>
we expand the driver to support more varied use cases.<br>
<br>
Cc: Sandeep Panda <<a href="mailto:spanda@codeaurora.org" target="_blank" rel="noreferrer">spanda@codeaurora.org</a>><br>
Signed-off-by: Sean Paul <<a href="mailto:seanpaul@chromium.org" target="_blank" rel="noreferrer">seanpaul@chromium.org</a>><br>
---<br>
 drivers/gpu/drm/bridge/ti-sn65dsi86.c | 107 ++++++++++++++++++++++++--<br>
 1 file changed, 100 insertions(+), 7 deletions(-)<br>
<br>
diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi86.c b/drivers/gpu/drm/bridge/ti-sn65dsi86.c<br>
index 1b6e8b72be58..50aa8c3c39fc 100644<br>
--- a/drivers/gpu/drm/bridge/ti-sn65dsi86.c<br>
+++ b/drivers/gpu/drm/bridge/ti-sn65dsi86.c<br>
@@ -7,12 +7,14 @@<br>
 #include <drm/drm_atomic.h><br>
 #include <drm/drm_atomic_helper.h><br>
 #include <drm/drm_crtc_helper.h><br>
+#include <drm/drm_dp_helper.h><br>
 #include <drm/drm_mipi_dsi.h><br>
 #include <drm/drm_of.h><br>
 #include <drm/drm_panel.h><br>
 #include <linux/clk.h><br>
 #include <linux/gpio/consumer.h><br>
 #include <linux/i2c.h><br>
+#include <linux/iopoll.h><br>
 #include <linux/of_graph.h><br>
 #include <linux/pm_runtime.h><br>
 #include <linux/regmap.h><br>
@@ -29,12 +31,15 @@<br>
 #define SN_DATARATE_CONFIG_REG                 0x94<br>
 #define SN_PLL_ENABLE_REG                      0x0D<br>
 #define SN_SCRAMBLE_CONFIG_REG                 0x95<br>
-#define SN_AUX_WDATA0_REG                      0x64<br>
+#define SN_AUX_WDATA_REG(x)                    (0x64 + x)<br>
 #define SN_AUX_ADDR_19_16_REG                  0x74<br>
 #define SN_AUX_ADDR_15_8_REG                   0x75<br>
 #define SN_AUX_ADDR_7_0_REG                    0x76<br>
 #define SN_AUX_LENGTH_REG                      0x77<br>
 #define SN_AUX_CMD_REG                         0x78<br>
+#define  AUX_CMD_SEND                          0x01<br>
+#define  AUX_CMD_REQ(x)                                (x << 4)<br>
+#define SN_AUX_RDATA_REG(x)                    (0x79 + x)<br>
 #define SN_ML_TX_MODE_REG                      0x96<br>
 /* video config specific registers */<br>
 #define SN_CHA_ACTIVE_LINE_LENGTH_LOW_REG      0x20<br>
@@ -64,6 +69,9 @@<br>
 #define SN_DP_DATA_RATE_OFFSET 5<br>
 #define SN_SYNC_POLARITY_OFFSET        7<br>
<br>
+/* Matches DP_AUX_MAX_PAYLOAD_BYTES (for now) */<br>
+#define SN_AUX_MAX_PAYLOAD_BYTES       16<br>
+<br>
 #define SN_ENABLE_VID_STREAM_BIT       BIT(3)<br>
 #define SN_REFCLK_FREQ_BITS            GENMASK(3, 1)<br>
 #define SN_DSIA_NUM_LANES_BITS         GENMASK(4, 3)<br>
@@ -76,6 +84,7 @@<br>
 struct ti_sn_bridge {<br>
        struct device                   *dev;<br>
        struct regmap                   *regmap;<br>
+       struct drm_dp_aux               aux;<br>
        struct drm_bridge               bridge;<br>
        struct drm_connector            connector;<br>
        struct device_node              *host_node;<br>
@@ -473,12 +482,7 @@ static void ti_sn_bridge_enable(struct drm_bridge *bridge)<br>
         * authentication method. We need to enable this method in the eDP panel<br>
         * at DisplayPort address 0x0010A prior to link training.<br>
         */<br>
-       regmap_write(pdata->regmap, SN_AUX_WDATA0_REG, 0x01);<br>
-       regmap_write(pdata->regmap, SN_AUX_ADDR_19_16_REG, 0x00);<br>
-       regmap_write(pdata->regmap, SN_AUX_ADDR_15_8_REG, 0x01);<br>
-       regmap_write(pdata->regmap, SN_AUX_ADDR_7_0_REG, 0x0A);<br>
-       regmap_write(pdata->regmap, SN_AUX_LENGTH_REG, 0x01);<br>
-       regmap_write(pdata->regmap, SN_AUX_CMD_REG, 0x81);<br>
+       drm_dp_dpcd_writeb(&pdata->aux, DP_EDP_CONFIGURATION_SET, 0);<br>
        usleep_range(10000, 10500); /* 10ms delay recommended by spec */<br>
<br>
        /* Semi auto link training mode */<br>
@@ -527,6 +531,90 @@ static const struct drm_bridge_funcs ti_sn_bridge_funcs = {<br>
        .post_disable = ti_sn_bridge_post_disable,<br>
 };<br>
<br>
+static struct ti_sn_bridge *aux_to_ti_sn_bridge(struct drm_dp_aux *aux)<br>
+{<br>
+       return container_of(aux, struct ti_sn_bridge, aux);<br>
+}<br>
+<br>
+static bool ti_sn_cmd_done(struct ti_sn_bridge *pdata)<br>
+{<br>
+       int ret;<br>
+       unsigned int val;<br>
+<br>
+       ret = regmap_read(pdata->regmap, SN_AUX_CMD_REG, &val);<br>
+       WARN_ON(ret);<br>
+       return ret || !(val & AUX_CMD_SEND);<br>
+}<br>
+<br>
+static ssize_t ti_sn_aux_transfer(struct drm_dp_aux *aux,<br>
+                                 struct drm_dp_aux_msg *msg)<br>
+{<br>
+       struct ti_sn_bridge *pdata = aux_to_ti_sn_bridge(aux);<br>
+       u32 request = msg->request & ~DP_AUX_I2C_MOT;<br>
+       u32 request_val = AUX_CMD_REQ(msg->request);<br>
+       u8 *buf = (u8 *)msg->buffer;<br>
+       bool cmd_done;<br>
+       int ret, i;<br>
+<br>
+       if (msg->size > SN_AUX_MAX_PAYLOAD_BYTES)<br>
+               return -EINVAL;<br>
+<br>
+       switch (request) {<br>
+       case DP_AUX_NATIVE_WRITE:<br>
+       case DP_AUX_I2C_WRITE:<br>
+       case DP_AUX_NATIVE_READ:<br>
+       case DP_AUX_I2C_READ:<br>
+               regmap_write(pdata->regmap, SN_AUX_CMD_REG, request_val);<br>
+               break;<br>
+       default:<br>
+               return -EINVAL;<br>
+       }<br>
+<br>
+       regmap_write(pdata->regmap, SN_AUX_ADDR_19_16_REG,<br>
+                    (msg->address >> 16) & 0xFF);<br>
+       regmap_write(pdata->regmap, SN_AUX_ADDR_15_8_REG,<br>
+                    (msg->address >> 8) & 0xFF);<br>
+       regmap_write(pdata->regmap, SN_AUX_ADDR_7_0_REG, msg->address & 0xFF);<br>
+<br>
+       regmap_write(pdata->regmap, SN_AUX_LENGTH_REG, msg->size);<br>
+<br>
+       if (request == DP_AUX_NATIVE_WRITE || request == DP_AUX_I2C_WRITE) {<br>
+               for (i = 0; i < msg->size; i++)<br>
+                       regmap_write(pdata->regmap, SN_AUX_WDATA_REG(i),<br>
+                                    buf[i]);<br>
+       }<br>
+<br>
+       regmap_write(pdata->regmap, SN_AUX_CMD_REG, request_val | AUX_CMD_SEND);<br>
+<br>
+       ret = readx_poll_timeout(ti_sn_cmd_done, pdata, cmd_done, cmd_done,<br>
+                                200, 50 * 1000);<br>
+       if (ret)<br>
+               return ret;<br>
+<br>
+       if (request == DP_AUX_NATIVE_READ || request == DP_AUX_I2C_READ) {<br>
+               unsigned int val;<br>
+<br>
+               ret = regmap_read(pdata->regmap, SN_AUX_LENGTH_REG, &val);<br>
+               if (ret)<br>
+                       return ret;<br>
+               else if (val != msg->size)<br>
+                       return -ENXIO;<br>
+<br>
+               for (i = 0; i < msg->size; i++) {<br>
+                       unsigned int val;<br>
+                       ret = regmap_read(pdata->regmap, SN_AUX_RDATA_REG(i),<br>
+                                         &val);<br>
+                       if (ret)<br>
+                               return ret;<br>
+<br>
+                       WARN_ON(val & ~0xFF);<br>
+                       buf[i] = (u8)(val & 0xFF);<br>
+               }<br>
+       }<br>
+<br>
+       return msg->size;<br>
+}<br>
+<br>
 static int ti_sn_bridge_parse_dsi_host(struct ti_sn_bridge *pdata)<br>
 {<br>
        struct device_node *np = pdata->dev->of_node;<br>
@@ -606,6 +694,11 @@ static int ti_sn_bridge_probe(struct i2c_client *client,<br>
<br>
        i2c_set_clientdata(client, pdata);<br>
<br>
+       pdata-><a href="http://aux.name" rel="noreferrer noreferrer" target="_blank">aux.name</a> = "ti-sn65dsi86-aux";<br>
+       pdata->aux.dev = pdata->dev;<br>
+       pdata->aux.transfer = ti_sn_aux_transfer;<br>
+       drm_dp_aux_register(&pdata->aux);<br>
+<br>
        pdata->bridge.funcs = &ti_sn_bridge_funcs;<br>
        pdata->bridge.of_node = client->dev.of_node;<br>
<br>
-- <br>
Sean Paul, Software Engineer, Google / Chromium OS<br>
<br>
</blockquote></div></div></div>