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path: root/drivers/gpu/drm/bridge/parade-ps8640.c
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Diffstat (limited to 'drivers/gpu/drm/bridge/parade-ps8640.c')
-rw-r--r--drivers/gpu/drm/bridge/parade-ps8640.c753
1 files changed, 753 insertions, 0 deletions
diff --git a/drivers/gpu/drm/bridge/parade-ps8640.c b/drivers/gpu/drm/bridge/parade-ps8640.c
new file mode 100644
index 000000000..14d4dcf23
--- /dev/null
+++ b/drivers/gpu/drm/bridge/parade-ps8640.c
@@ -0,0 +1,753 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2016 MediaTek Inc.
+ */
+
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#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/display/drm_dp_aux_bus.h>
+#include <drm/display/drm_dp_helper.h>
+#include <drm/drm_atomic_state_helper.h>
+#include <drm/drm_bridge.h>
+#include <drm/drm_edid.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_SWAUX_ADDR_7_0 0x7d
+#define PAGE0_SWAUX_ADDR_15_8 0x7e
+#define PAGE0_SWAUX_ADDR_23_16 0x7f
+#define SWAUX_ADDR_MASK GENMASK(19, 0)
+#define PAGE0_SWAUX_LENGTH 0x80
+#define SWAUX_LENGTH_MASK GENMASK(3, 0)
+#define SWAUX_NO_PAYLOAD BIT(7)
+#define PAGE0_SWAUX_WDATA 0x81
+#define PAGE0_SWAUX_RDATA 0x82
+#define PAGE0_SWAUX_CTRL 0x83
+#define SWAUX_SEND BIT(0)
+#define PAGE0_SWAUX_STATUS 0x84
+#define SWAUX_M_MASK GENMASK(4, 0)
+#define SWAUX_STATUS_MASK GENMASK(7, 5)
+#define SWAUX_STATUS_NACK (0x1 << 5)
+#define SWAUX_STATUS_DEFER (0x2 << 5)
+#define SWAUX_STATUS_ACKM (0x3 << 5)
+#define SWAUX_STATUS_INVALID (0x4 << 5)
+#define SWAUX_STATUS_I2C_NACK (0x5 << 5)
+#define SWAUX_STATUS_I2C_DEFER (0x6 << 5)
+#define SWAUX_STATUS_TIMEOUT (0x7 << 5)
+
+#define PAGE2_GPIO_H 0xa7
+#define PS_GPIO9 BIT(1)
+#define PAGE2_I2C_BYPASS 0xea
+#define I2C_BYPASS_EN 0xd0
+#define PAGE2_MCS_EN 0xf3
+#define MCS_EN BIT(0)
+
+#define PAGE3_SET_ADD 0xfe
+#define VDO_CTL_ADD 0x13
+#define VDO_DIS 0x18
+#define VDO_EN 0x1c
+
+#define NUM_MIPI_LANES 4
+
+#define COMMON_PS8640_REGMAP_CONFIG \
+ .reg_bits = 8, \
+ .val_bits = 8, \
+ .cache_type = REGCACHE_NONE
+
+/*
+ * PS8640 uses multiple addresses:
+ * page[0]: for DP control
+ * page[1]: for VIDEO Bridge
+ * page[2]: for control top
+ * page[3]: for DSI Link Control1
+ * page[4]: for MIPI Phy
+ * page[5]: for VPLL
+ * page[6]: for DSI Link Control2
+ * page[7]: for SPI ROM mapping
+ */
+enum page_addr_offset {
+ PAGE0_DP_CNTL = 0,
+ PAGE1_VDO_BDG,
+ PAGE2_TOP_CNTL,
+ PAGE3_DSI_CNTL1,
+ PAGE4_MIPI_PHY,
+ PAGE5_VPLL,
+ PAGE6_DSI_CNTL2,
+ PAGE7_SPI_CNTL,
+ MAX_DEVS
+};
+
+enum ps8640_vdo_control {
+ DISABLE = VDO_DIS,
+ ENABLE = VDO_EN,
+};
+
+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];
+ struct regulator_bulk_data supplies[2];
+ struct gpio_desc *gpio_reset;
+ struct gpio_desc *gpio_powerdown;
+ struct device_link *link;
+ bool pre_enabled;
+ bool need_post_hpd_delay;
+ struct mutex aux_lock;
+};
+
+static const struct regmap_config ps8640_regmap_config[] = {
+ [PAGE0_DP_CNTL] = {
+ COMMON_PS8640_REGMAP_CONFIG,
+ .max_register = 0xbf,
+ },
+ [PAGE1_VDO_BDG] = {
+ COMMON_PS8640_REGMAP_CONFIG,
+ .max_register = 0xff,
+ },
+ [PAGE2_TOP_CNTL] = {
+ COMMON_PS8640_REGMAP_CONFIG,
+ .max_register = 0xff,
+ },
+ [PAGE3_DSI_CNTL1] = {
+ COMMON_PS8640_REGMAP_CONFIG,
+ .max_register = 0xff,
+ },
+ [PAGE4_MIPI_PHY] = {
+ COMMON_PS8640_REGMAP_CONFIG,
+ .max_register = 0xff,
+ },
+ [PAGE5_VPLL] = {
+ COMMON_PS8640_REGMAP_CONFIG,
+ .max_register = 0x7f,
+ },
+ [PAGE6_DSI_CNTL2] = {
+ COMMON_PS8640_REGMAP_CONFIG,
+ .max_register = 0xff,
+ },
+ [PAGE7_SPI_CNTL] = {
+ COMMON_PS8640_REGMAP_CONFIG,
+ .max_register = 0xff,
+ },
+};
+
+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 int _ps8640_wait_hpd_asserted(struct ps8640 *ps_bridge, unsigned long wait_us)
+{
+ struct regmap *map = ps_bridge->regmap[PAGE2_TOP_CNTL];
+ int status;
+ int ret;
+
+ /*
+ * Apparently something about the firmware in the chip signals that
+ * HPD goes high by reporting GPIO9 as high (even though HPD isn't
+ * actually connected to GPIO9).
+ */
+ ret = regmap_read_poll_timeout(map, PAGE2_GPIO_H, status,
+ status & PS_GPIO9, 20000, wait_us);
+
+ /*
+ * The first time we see HPD go high after a reset we delay an extra
+ * 50 ms. The best guess is that the MCU is doing "stuff" during this
+ * time (maybe talking to the panel) and we don't want to interrupt it.
+ *
+ * No locking is done around "need_post_hpd_delay". If we're here we
+ * know we're holding a PM Runtime reference and the only other place
+ * that touches this is PM Runtime resume.
+ */
+ if (!ret && ps_bridge->need_post_hpd_delay) {
+ ps_bridge->need_post_hpd_delay = false;
+ msleep(50);
+ }
+
+ return ret;
+}
+
+static int ps8640_wait_hpd_asserted(struct drm_dp_aux *aux, unsigned long wait_us)
+{
+ struct ps8640 *ps_bridge = aux_to_ps8640(aux);
+ struct device *dev = &ps_bridge->page[PAGE0_DP_CNTL]->dev;
+ int ret;
+
+ /*
+ * Note that this function is called by code that has already powered
+ * the panel. We have to power ourselves up but we don't need to worry
+ * about powering the panel.
+ */
+ pm_runtime_get_sync(dev);
+ ret = _ps8640_wait_hpd_asserted(ps_bridge, wait_us);
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);
+
+ return ret;
+}
+
+static ssize_t ps8640_aux_transfer_msg(struct drm_dp_aux *aux,
+ struct drm_dp_aux_msg *msg)
+{
+ struct ps8640 *ps_bridge = aux_to_ps8640(aux);
+ struct regmap *map = ps_bridge->regmap[PAGE0_DP_CNTL];
+ struct device *dev = &ps_bridge->page[PAGE0_DP_CNTL]->dev;
+ size_t len = msg->size;
+ unsigned int data;
+ unsigned int base;
+ int ret;
+ u8 request = msg->request &
+ ~(DP_AUX_I2C_MOT | DP_AUX_I2C_WRITE_STATUS_UPDATE);
+ u8 *buf = msg->buffer;
+ u8 addr_len[PAGE0_SWAUX_LENGTH + 1 - PAGE0_SWAUX_ADDR_7_0];
+ u8 i;
+ bool is_native_aux = false;
+
+ if (len > DP_AUX_MAX_PAYLOAD_BYTES)
+ return -EINVAL;
+
+ if (msg->address & ~SWAUX_ADDR_MASK)
+ return -EINVAL;
+
+ switch (request) {
+ case DP_AUX_NATIVE_WRITE:
+ case DP_AUX_NATIVE_READ:
+ is_native_aux = true;
+ fallthrough;
+ case DP_AUX_I2C_WRITE:
+ case DP_AUX_I2C_READ:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ ret = regmap_write(map, PAGE0_AUXCH_CFG3, AUXCH_CFG3_RESET);
+ if (ret) {
+ DRM_DEV_ERROR(dev, "failed to write PAGE0_AUXCH_CFG3: %d\n",
+ ret);
+ return ret;
+ }
+
+ /* Assume it's good */
+ msg->reply = 0;
+
+ base = PAGE0_SWAUX_ADDR_7_0;
+ addr_len[PAGE0_SWAUX_ADDR_7_0 - base] = msg->address;
+ addr_len[PAGE0_SWAUX_ADDR_15_8 - base] = msg->address >> 8;
+ addr_len[PAGE0_SWAUX_ADDR_23_16 - base] = (msg->address >> 16) |
+ (msg->request << 4);
+ addr_len[PAGE0_SWAUX_LENGTH - base] = (len == 0) ? SWAUX_NO_PAYLOAD :
+ ((len - 1) & SWAUX_LENGTH_MASK);
+
+ regmap_bulk_write(map, PAGE0_SWAUX_ADDR_7_0, addr_len,
+ ARRAY_SIZE(addr_len));
+
+ if (len && (request == DP_AUX_NATIVE_WRITE ||
+ request == DP_AUX_I2C_WRITE)) {
+ /* Write to the internal FIFO buffer */
+ for (i = 0; i < len; i++) {
+ ret = regmap_write(map, PAGE0_SWAUX_WDATA, buf[i]);
+ if (ret) {
+ DRM_DEV_ERROR(dev,
+ "failed to write WDATA: %d\n",
+ ret);
+ return ret;
+ }
+ }
+ }
+
+ regmap_write(map, PAGE0_SWAUX_CTRL, SWAUX_SEND);
+
+ /* Zero delay loop because i2c transactions are slow already */
+ regmap_read_poll_timeout(map, PAGE0_SWAUX_CTRL, data,
+ !(data & SWAUX_SEND), 0, 50 * 1000);
+
+ regmap_read(map, PAGE0_SWAUX_STATUS, &data);
+ if (ret) {
+ DRM_DEV_ERROR(dev, "failed to read PAGE0_SWAUX_STATUS: %d\n",
+ ret);
+ return ret;
+ }
+
+ switch (data & SWAUX_STATUS_MASK) {
+ case SWAUX_STATUS_NACK:
+ case SWAUX_STATUS_I2C_NACK:
+ /*
+ * The programming guide is not clear about whether a I2C NACK
+ * would trigger SWAUX_STATUS_NACK or SWAUX_STATUS_I2C_NACK. So
+ * we handle both cases together.
+ */
+ if (is_native_aux)
+ msg->reply |= DP_AUX_NATIVE_REPLY_NACK;
+ else
+ msg->reply |= DP_AUX_I2C_REPLY_NACK;
+
+ fallthrough;
+ case SWAUX_STATUS_ACKM:
+ len = data & SWAUX_M_MASK;
+ break;
+ case SWAUX_STATUS_DEFER:
+ case SWAUX_STATUS_I2C_DEFER:
+ if (is_native_aux)
+ msg->reply |= DP_AUX_NATIVE_REPLY_DEFER;
+ else
+ msg->reply |= DP_AUX_I2C_REPLY_DEFER;
+ len = data & SWAUX_M_MASK;
+ break;
+ case SWAUX_STATUS_INVALID:
+ return -EOPNOTSUPP;
+ case SWAUX_STATUS_TIMEOUT:
+ return -ETIMEDOUT;
+ }
+
+ if (len && (request == DP_AUX_NATIVE_READ ||
+ request == DP_AUX_I2C_READ)) {
+ /* Read from the internal FIFO buffer */
+ for (i = 0; i < len; i++) {
+ ret = regmap_read(map, PAGE0_SWAUX_RDATA, &data);
+ if (ret) {
+ DRM_DEV_ERROR(dev,
+ "failed to read RDATA: %d\n",
+ ret);
+ return ret;
+ }
+
+ if (i < msg->size)
+ buf[i] = data;
+ }
+ }
+
+ return min(len, msg->size);
+}
+
+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 device *dev = &ps_bridge->page[PAGE0_DP_CNTL]->dev;
+ int ret;
+
+ mutex_lock(&ps_bridge->aux_lock);
+ pm_runtime_get_sync(dev);
+ ret = _ps8640_wait_hpd_asserted(ps_bridge, 200 * 1000);
+ if (ret) {
+ pm_runtime_put_sync_suspend(dev);
+ goto exit;
+ }
+ ret = ps8640_aux_transfer_msg(aux, msg);
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);
+
+exit:
+ mutex_unlock(&ps_bridge->aux_lock);
+
+ return ret;
+}
+
+static void ps8640_bridge_vdo_control(struct ps8640 *ps_bridge,
+ const enum ps8640_vdo_control ctrl)
+{
+ struct regmap *map = ps_bridge->regmap[PAGE3_DSI_CNTL1];
+ struct device *dev = &ps_bridge->page[PAGE3_DSI_CNTL1]->dev;
+ u8 vdo_ctrl_buf[] = { VDO_CTL_ADD, ctrl };
+ int ret;
+
+ ret = regmap_bulk_write(map, PAGE3_SET_ADD,
+ vdo_ctrl_buf, sizeof(vdo_ctrl_buf));
+
+ if (ret < 0)
+ dev_err(dev, "failed to %sable VDO: %d\n",
+ ctrl == ENABLE ? "en" : "dis", ret);
+}
+
+static int __maybe_unused ps8640_resume(struct device *dev)
+{
+ struct ps8640 *ps_bridge = dev_get_drvdata(dev);
+ int ret;
+
+ ret = regulator_bulk_enable(ARRAY_SIZE(ps_bridge->supplies),
+ ps_bridge->supplies);
+ if (ret < 0) {
+ dev_err(dev, "cannot enable regulators %d\n", ret);
+ return ret;
+ }
+
+ gpiod_set_value(ps_bridge->gpio_powerdown, 0);
+ gpiod_set_value(ps_bridge->gpio_reset, 1);
+ usleep_range(2000, 2500);
+ gpiod_set_value(ps_bridge->gpio_reset, 0);
+ /* Double reset for T4 and T5 */
+ msleep(50);
+ gpiod_set_value(ps_bridge->gpio_reset, 1);
+ msleep(50);
+ gpiod_set_value(ps_bridge->gpio_reset, 0);
+
+ /* We just reset things, so we need a delay after the first HPD */
+ ps_bridge->need_post_hpd_delay = true;
+
+ /*
+ * Mystery 200 ms delay for the "MCU to be ready". It's unclear if
+ * this is truly necessary since the MCU will already signal that
+ * things are "good to go" by signaling HPD on "gpio 9". See
+ * _ps8640_wait_hpd_asserted(). For now we'll keep this mystery delay
+ * just in case.
+ */
+ msleep(200);
+
+ return 0;
+}
+
+static int __maybe_unused ps8640_suspend(struct device *dev)
+{
+ struct ps8640 *ps_bridge = dev_get_drvdata(dev);
+ int ret;
+
+ gpiod_set_value(ps_bridge->gpio_reset, 1);
+ gpiod_set_value(ps_bridge->gpio_powerdown, 1);
+ ret = regulator_bulk_disable(ARRAY_SIZE(ps_bridge->supplies),
+ ps_bridge->supplies);
+ if (ret < 0)
+ dev_err(dev, "cannot disable regulators %d\n", ret);
+
+ return ret;
+}
+
+static const struct dev_pm_ops ps8640_pm_ops = {
+ SET_RUNTIME_PM_OPS(ps8640_suspend, ps8640_resume, NULL)
+ SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+};
+
+static void ps8640_atomic_pre_enable(struct drm_bridge *bridge,
+ struct drm_bridge_state *old_bridge_state)
+{
+ struct ps8640 *ps_bridge = bridge_to_ps8640(bridge);
+ struct regmap *map = ps_bridge->regmap[PAGE2_TOP_CNTL];
+ struct device *dev = &ps_bridge->page[PAGE0_DP_CNTL]->dev;
+ int ret;
+
+ pm_runtime_get_sync(dev);
+ ret = _ps8640_wait_hpd_asserted(ps_bridge, 200 * 1000);
+ if (ret < 0)
+ dev_warn(dev, "HPD didn't go high: %d\n", ret);
+
+ /*
+ * The Manufacturer Command Set (MCS) is a device dependent interface
+ * intended for factory programming of the display module default
+ * parameters. Once the display module is configured, the MCS shall be
+ * disabled by the manufacturer. Once disabled, all MCS commands are
+ * ignored by the display interface.
+ */
+
+ ret = regmap_update_bits(map, PAGE2_MCS_EN, MCS_EN, 0);
+ if (ret < 0)
+ dev_warn(dev, "failed write PAGE2_MCS_EN: %d\n", ret);
+
+ /* Switch access edp panel's edid through i2c */
+ ret = regmap_write(map, PAGE2_I2C_BYPASS, I2C_BYPASS_EN);
+ if (ret < 0)
+ dev_warn(dev, "failed write PAGE2_MCS_EN: %d\n", ret);
+
+ ps8640_bridge_vdo_control(ps_bridge, ENABLE);
+
+ ps_bridge->pre_enabled = true;
+}
+
+static void ps8640_atomic_post_disable(struct drm_bridge *bridge,
+ struct drm_bridge_state *old_bridge_state)
+{
+ struct ps8640 *ps_bridge = bridge_to_ps8640(bridge);
+
+ ps_bridge->pre_enabled = false;
+
+ ps8640_bridge_vdo_control(ps_bridge, DISABLE);
+
+ /*
+ * The bridge seems to expect everything to be power cycled at the
+ * disable process, so grab a lock here to make sure
+ * ps8640_aux_transfer() is not holding a runtime PM reference and
+ * preventing the bridge from suspend.
+ */
+ mutex_lock(&ps_bridge->aux_lock);
+
+ pm_runtime_put_sync_suspend(&ps_bridge->page[PAGE0_DP_CNTL]->dev);
+
+ mutex_unlock(&ps_bridge->aux_lock);
+}
+
+static int ps8640_bridge_attach(struct drm_bridge *bridge,
+ enum drm_bridge_attach_flags flags)
+{
+ struct ps8640 *ps_bridge = bridge_to_ps8640(bridge);
+ struct device *dev = &ps_bridge->page[0]->dev;
+ int ret;
+
+ if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
+ return -EINVAL;
+
+ ps_bridge->aux.drm_dev = bridge->dev;
+ ret = drm_dp_aux_register(&ps_bridge->aux);
+ if (ret) {
+ dev_err(dev, "failed to register DP AUX channel: %d\n", ret);
+ return ret;
+ }
+
+ ps_bridge->link = device_link_add(bridge->dev->dev, dev, DL_FLAG_STATELESS);
+ if (!ps_bridge->link) {
+ dev_err(dev, "failed to create device link");
+ ret = -EINVAL;
+ goto err_devlink;
+ }
+
+ /* Attach the panel-bridge to the dsi bridge */
+ ret = drm_bridge_attach(bridge->encoder, ps_bridge->panel_bridge,
+ &ps_bridge->bridge, flags);
+ if (ret)
+ goto err_bridge_attach;
+
+ return 0;
+
+err_bridge_attach:
+ device_link_del(ps_bridge->link);
+err_devlink:
+ drm_dp_aux_unregister(&ps_bridge->aux);
+
+ return ret;
+}
+
+static void ps8640_bridge_detach(struct drm_bridge *bridge)
+{
+ struct ps8640 *ps_bridge = bridge_to_ps8640(bridge);
+
+ drm_dp_aux_unregister(&ps_bridge->aux);
+ if (ps_bridge->link)
+ device_link_del(ps_bridge->link);
+}
+
+static void ps8640_runtime_disable(void *data)
+{
+ pm_runtime_dont_use_autosuspend(data);
+ pm_runtime_disable(data);
+}
+
+static const struct drm_bridge_funcs ps8640_bridge_funcs = {
+ .attach = ps8640_bridge_attach,
+ .detach = ps8640_bridge_detach,
+ .atomic_post_disable = ps8640_atomic_post_disable,
+ .atomic_pre_enable = ps8640_atomic_pre_enable,
+ .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
+ .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
+ .atomic_reset = drm_atomic_helper_bridge_reset,
+};
+
+static int ps8640_bridge_get_dsi_resources(struct device *dev, struct ps8640 *ps_bridge)
+{
+ struct device_node *in_ep, *dsi_node;
+ struct mipi_dsi_device *dsi;
+ struct mipi_dsi_host *host;
+ const struct mipi_dsi_device_info info = { .type = "ps8640",
+ .channel = 0,
+ .node = NULL,
+ };
+
+ /* port@0 is ps8640 dsi input port */
+ in_ep = of_graph_get_endpoint_by_regs(dev->of_node, 0, -1);
+ if (!in_ep)
+ return -ENODEV;
+
+ dsi_node = of_graph_get_remote_port_parent(in_ep);
+ of_node_put(in_ep);
+ if (!dsi_node)
+ return -ENODEV;
+
+ host = of_find_mipi_dsi_host_by_node(dsi_node);
+ of_node_put(dsi_node);
+ if (!host)
+ return -EPROBE_DEFER;
+
+ dsi = devm_mipi_dsi_device_register_full(dev, host, &info);
+ if (IS_ERR(dsi)) {
+ dev_err(dev, "failed to create dsi device\n");
+ return PTR_ERR(dsi);
+ }
+
+ ps_bridge->dsi = dsi;
+
+ dsi->host = host;
+ dsi->mode_flags = MIPI_DSI_MODE_VIDEO |
+ MIPI_DSI_MODE_VIDEO_SYNC_PULSE;
+ dsi->format = MIPI_DSI_FMT_RGB888;
+ dsi->lanes = NUM_MIPI_LANES;
+
+ return 0;
+}
+
+static int ps8640_bridge_link_panel(struct drm_dp_aux *aux)
+{
+ struct ps8640 *ps_bridge = aux_to_ps8640(aux);
+ struct device *dev = aux->dev;
+ struct device_node *np = dev->of_node;
+ int ret;
+
+ /*
+ * NOTE about returning -EPROBE_DEFER from this function: if we
+ * return an error (most relevant to -EPROBE_DEFER) it will only
+ * be passed out to ps8640_probe() if it called this directly (AKA the
+ * panel isn't under the "aux-bus" node). That should be fine because
+ * if the panel is under "aux-bus" it's guaranteed to have probed by
+ * the time this function has been called.
+ */
+
+ /* port@1 is ps8640 output port */
+ ps_bridge->panel_bridge = devm_drm_of_get_bridge(dev, np, 1, 0);
+ if (IS_ERR(ps_bridge->panel_bridge))
+ return PTR_ERR(ps_bridge->panel_bridge);
+
+ ret = devm_drm_bridge_add(dev, &ps_bridge->bridge);
+ if (ret)
+ return ret;
+
+ return devm_mipi_dsi_attach(dev, ps_bridge->dsi);
+}
+
+static int ps8640_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct ps8640 *ps_bridge;
+ int ret;
+ u32 i;
+
+ ps_bridge = devm_kzalloc(dev, sizeof(*ps_bridge), GFP_KERNEL);
+ if (!ps_bridge)
+ return -ENOMEM;
+
+ mutex_init(&ps_bridge->aux_lock);
+
+ ps_bridge->supplies[0].supply = "vdd12";
+ ps_bridge->supplies[1].supply = "vdd33";
+ ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ps_bridge->supplies),
+ ps_bridge->supplies);
+ if (ret)
+ return ret;
+
+ ps_bridge->gpio_powerdown = devm_gpiod_get(&client->dev, "powerdown",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(ps_bridge->gpio_powerdown))
+ return PTR_ERR(ps_bridge->gpio_powerdown);
+
+ /*
+ * Assert the reset to avoid the bridge being initialized prematurely
+ */
+ ps_bridge->gpio_reset = devm_gpiod_get(&client->dev, "reset",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(ps_bridge->gpio_reset))
+ return PTR_ERR(ps_bridge->gpio_reset);
+
+ ps_bridge->bridge.funcs = &ps8640_bridge_funcs;
+ ps_bridge->bridge.of_node = dev->of_node;
+ ps_bridge->bridge.type = DRM_MODE_CONNECTOR_eDP;
+
+ /*
+ * Get MIPI DSI resources early. These can return -EPROBE_DEFER so
+ * we want to get them out of the way sooner.
+ */
+ ret = ps8640_bridge_get_dsi_resources(&client->dev, ps_bridge);
+ if (ret)
+ return ret;
+
+ ps_bridge->page[PAGE0_DP_CNTL] = client;
+
+ ps_bridge->regmap[PAGE0_DP_CNTL] = devm_regmap_init_i2c(client, ps8640_regmap_config);
+ if (IS_ERR(ps_bridge->regmap[PAGE0_DP_CNTL]))
+ return PTR_ERR(ps_bridge->regmap[PAGE0_DP_CNTL]);
+
+ for (i = 1; i < ARRAY_SIZE(ps_bridge->page); i++) {
+ ps_bridge->page[i] = devm_i2c_new_dummy_device(&client->dev,
+ client->adapter,
+ client->addr + i);
+ if (IS_ERR(ps_bridge->page[i]))
+ return PTR_ERR(ps_bridge->page[i]);
+
+ ps_bridge->regmap[i] = devm_regmap_init_i2c(ps_bridge->page[i],
+ ps8640_regmap_config + i);
+ if (IS_ERR(ps_bridge->regmap[i]))
+ return PTR_ERR(ps_bridge->regmap[i]);
+ }
+
+ 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;
+ ps_bridge->aux.wait_hpd_asserted = ps8640_wait_hpd_asserted;
+ drm_dp_aux_init(&ps_bridge->aux);
+
+ pm_runtime_enable(dev);
+ /*
+ * Powering on ps8640 takes ~300ms. To avoid wasting time on power
+ * cycling ps8640 too often, set autosuspend_delay to 2000ms to ensure
+ * the bridge wouldn't suspend in between each _aux_transfer_msg() call
+ * during EDID read (~20ms in my experiment) and in between the last
+ * _aux_transfer_msg() call during EDID read and the _pre_enable() call
+ * (~100ms in my experiment).
+ */
+ pm_runtime_set_autosuspend_delay(dev, 2000);
+ pm_runtime_use_autosuspend(dev);
+ pm_suspend_ignore_children(dev, true);
+ ret = devm_add_action_or_reset(dev, ps8640_runtime_disable, dev);
+ if (ret)
+ return ret;
+
+ ret = devm_of_dp_aux_populate_bus(&ps_bridge->aux, ps8640_bridge_link_panel);
+
+ /*
+ * If devm_of_dp_aux_populate_bus() returns -ENODEV then it's up to
+ * usa to call ps8640_bridge_link_panel() directly. NOTE: in this case
+ * the function is allowed to -EPROBE_DEFER.
+ */
+ if (ret == -ENODEV)
+ return ps8640_bridge_link_panel(&ps_bridge->aux);
+
+ return ret;
+}
+
+static const struct of_device_id ps8640_match[] = {
+ { .compatible = "parade,ps8640" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ps8640_match);
+
+static struct i2c_driver ps8640_driver = {
+ .probe = ps8640_probe,
+ .driver = {
+ .name = "ps8640",
+ .of_match_table = ps8640_match,
+ .pm = &ps8640_pm_ops,
+ },
+};
+module_i2c_driver(ps8640_driver);
+
+MODULE_AUTHOR("Jitao Shi <jitao.shi@mediatek.com>");
+MODULE_AUTHOR("CK Hu <ck.hu@mediatek.com>");
+MODULE_AUTHOR("Enric Balletbo i Serra <enric.balletbo@collabora.com>");
+MODULE_DESCRIPTION("PARADE ps8640 DSI-eDP converter driver");
+MODULE_LICENSE("GPL v2");