Implement the first version of AUX support, which will be useful as
we expand the driver to support varied use cases.
Signed-off-by: Philip Chen <philipchen@xxxxxxxxxxxx>
---
drivers/gpu/drm/bridge/parade-ps8640.c | 123 +++++++++++++++++++++++++
1 file changed, 123 insertions(+)
diff --git a/drivers/gpu/drm/bridge/parade-ps8640.c b/drivers/gpu/drm/bridge/parade-ps8640.c
index a16725dbf912..3f0241a60357 100644
--- a/drivers/gpu/drm/bridge/parade-ps8640.c
+++ b/drivers/gpu/drm/bridge/parade-ps8640.c
@@ -9,15 +9,36 @@
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/of_graph.h>
+#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <drm/drm_bridge.h>
+#include <drm/drm_dp_helper.h>
#include <drm/drm_mipi_dsi.h>
#include <drm/drm_of.h>
#include <drm/drm_panel.h>
#include <drm/drm_print.h>
+#define PAGE0_AUXCH_CFG3 0x76
+#define AUXCH_CFG3_RESET 0xff
+#define PAGE0_AUX_ADDR_7_0 0x7d
+#define PAGE0_AUX_ADDR_15_8 0x7e
+#define PAGE0_AUX_ADDR_23_16 0x7f
+#define AUX_ADDR_19_16_MASK GENMASK(3, 0)
+#define AUX_CMD_MASK GENMASK(7, 4)
+#define PAGE0_AUX_LENGTH 0x80
+#define AUX_LENGTH_MASK GENMASK(3, 0)
+#define PAGE0_AUX_WDATA 0x81
+#define PAGE0_AUX_RDATA 0x82
+#define PAGE0_AUX_CTRL 0x83
+#define AUX_START 0x01
+#define PAGE0_AUX_STATUS 0x84
+#define AUX_STATUS_MASK GENMASK(7, 5)
+#define AUX_STATUS_TIMEOUT (0x7 << 5)
+#define AUX_STATUS_DEFER (0x2 << 5)
+#define AUX_STATUS_NACK (0x1 << 5)
+
#define PAGE2_GPIO_H 0xa7
#define PS_GPIO9 BIT(1)
#define PAGE2_I2C_BYPASS 0xea
@@ -63,6 +84,7 @@ enum ps8640_vdo_control {
struct ps8640 {
struct drm_bridge bridge;
struct drm_bridge *panel_bridge;
+ struct drm_dp_aux aux;
struct mipi_dsi_device *dsi;
struct i2c_client *page[MAX_DEVS];
struct regmap *regmap[MAX_DEVS];
@@ -93,6 +115,102 @@ static inline struct ps8640 *bridge_to_ps8640(struct drm_bridge *e)
return container_of(e, struct ps8640, bridge);
}
+static inline struct ps8640 *aux_to_ps8640(struct drm_dp_aux *aux)
+{
+ return container_of(aux, struct ps8640, aux);
+}
+
+static ssize_t ps8640_aux_transfer(struct drm_dp_aux *aux,
+ struct drm_dp_aux_msg *msg)
+{
+ struct ps8640 *ps_bridge = aux_to_ps8640(aux);
+ struct i2c_client *client = ps_bridge->page[PAGE0_DP_CNTL];
+ struct regmap *map = ps_bridge->regmap[PAGE0_DP_CNTL];
+ unsigned int len = msg->size;
+ unsigned int data;
+ int ret;
+ u8 request = msg->request &
+ ~(DP_AUX_I2C_MOT | DP_AUX_I2C_WRITE_STATUS_UPDATE);
+ u8 *buf = msg->buffer;
+ bool is_native_aux = false;
+
+ if (len > DP_AUX_MAX_PAYLOAD_BYTES)
+ return -EINVAL;
+
+ pm_runtime_get_sync(&client->dev);
+
+ switch (request) {
+ case DP_AUX_NATIVE_WRITE:
+ case DP_AUX_NATIVE_READ:
+ is_native_aux = true;
+ case DP_AUX_I2C_WRITE:
+ case DP_AUX_I2C_READ:
+ regmap_write(map, PAGE0_AUXCH_CFG3, AUXCH_CFG3_RESET);
+ break;
+ default:
+ ret = -EINVAL;
+ goto exit;
+ }
+
+ /* Assume it's good */
+ msg->reply = 0;
+
+ data = ((request << 4) & AUX_CMD_MASK) |
+ ((msg->address >> 16) & AUX_ADDR_19_16_MASK);
+ regmap_write(map, PAGE0_AUX_ADDR_23_16, data);
+ data = (msg->address >> 8) & 0xff;
+ regmap_write(map, PAGE0_AUX_ADDR_15_8, data);
+ data = msg->address & 0xff;
+ regmap_write(map, PAGE0_AUX_ADDR_7_0, msg->address & 0xff);
+
+ data = (len - 1) & AUX_LENGTH_MASK;
+ regmap_write(map, PAGE0_AUX_LENGTH, data);
+
+ if (request == DP_AUX_NATIVE_WRITE || request == DP_AUX_I2C_WRITE) {
+ ret = regmap_noinc_write(map, PAGE0_AUX_WDATA, buf, len);
+ if (ret < 0) {
+ DRM_ERROR("failed to write PAGE0_AUX_WDATA");
+ goto exit;
+ }
+ }
+
+ regmap_write(map, PAGE0_AUX_CTRL, AUX_START);
+
+ regmap_read(map, PAGE0_AUX_STATUS, &data);
+ switch (data & AUX_STATUS_MASK) {
+ case AUX_STATUS_DEFER:
+ if (is_native_aux)
+ msg->reply |= DP_AUX_NATIVE_REPLY_DEFER;
+ else
+ msg->reply |= DP_AUX_I2C_REPLY_DEFER;
+ goto exit;
+ case AUX_STATUS_NACK:
+ if (is_native_aux)
+ msg->reply |= DP_AUX_NATIVE_REPLY_NACK;
+ else
+ msg->reply |= DP_AUX_I2C_REPLY_NACK;
+ goto exit;
+ case AUX_STATUS_TIMEOUT:
+ ret = -ETIMEDOUT;
+ goto exit;
+ }
+
+ if (request == DP_AUX_NATIVE_READ || request == DP_AUX_I2C_READ) {
+ ret = regmap_noinc_read(map, PAGE0_AUX_RDATA, buf, len);
+ if (ret < 0)
+ DRM_ERROR("failed to read PAGE0_AUX_RDATA");
+ }
+
+exit:
+ pm_runtime_mark_last_busy(&client->dev);
+ pm_runtime_put_autosuspend(&client->dev);
+
+ if (ret)
+ return ret;
+
+ return len;
+}
+
static int ps8640_bridge_vdo_control(struct ps8640 *ps_bridge,
const enum ps8640_vdo_control ctrl)
{
@@ -387,6 +505,11 @@ static int ps8640_probe(struct i2c_client *client)
i2c_set_clientdata(client, ps_bridge);
+ ps_bridge->aux.name = "parade-ps8640-aux";
+ ps_bridge->aux.dev = dev;
+ ps_bridge->aux.transfer = ps8640_aux_transfer;
+ drm_dp_aux_init(&ps_bridge->aux);
+
drm_bridge_add(&ps_bridge->bridge);
return 0;
--
2.33.0.153.gba50c8fa24-goog
