[PATCH v14 2/2] drm/bridge: Add I2C based driver for ps8640 bridge
Jitao Shi
jitao.shi at mediatek.com
Wed Apr 27 18:32:48 PDT 2016
On Thu, 2016-04-14 at 16:28 +0200, Thierry Reding wrote:
> On Sun, Apr 03, 2016 at 12:20:45PM +0800, Jitao Shi wrote:
> [...]
> > diff --git a/drivers/gpu/drm/bridge/parade-ps8640.c b/drivers/gpu/drm/bridge/parade-ps8640.c
> > new file mode 100644
> > index 0000000..87f8bc7
> > --- /dev/null
> > +++ b/drivers/gpu/drm/bridge/parade-ps8640.c
> > @@ -0,0 +1,1066 @@
> > +/*
> > + * Copyright (c) 2014 MediaTek Inc.
>
> Presumably the copyright here should be updated?
Thanks for your review. I'll update it next version.
>
> > +#include <linux/delay.h>
> > +#include <linux/err.h>
> > +#include <linux/firmware.h>
> > +#include <linux/gpio.h>
> > +#include <linux/gpio/consumer.h>
> > +#include <linux/i2c.h>
> > +#include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/of_gpio.h>
> > +#include <linux/of_graph.h>
> > +#include <linux/regulator/consumer.h>
> > +#include <asm/unaligned.h>
> > +#include <drm/drm_panel.h>
> > +
> > +#include <drmP.h>
> > +#include <drm_atomic_helper.h>
> > +#include <drm_crtc_helper.h>
> > +#include <drm_crtc.h>
> > +#include <drm_edid.h>
> > +#include <drm_mipi_dsi.h>
> > +
> > +#define PAGE2_SPI_CFG3 0x82
> > +#define I2C_TO_SPI_RESET 0x20
> > +#define PAGE2_ROMADD_BYTE1 0x8e
> > +#define PAGE2_ROMADD_BYTE2 0x8f
> > +#define PAGE2_SWSPI_WDATA 0x90
> > +#define PAGE2_SWSPI_RDATA 0x91
> > +#define PAGE2_SWSPI_LEN 0x92
> > +#define PAGE2_SWSPI_CTL 0x93
> > +#define TRIGGER_NO_READBACK 0x05
> > +#define TRIGGER_READBACK 0x01
> > +#define PAGE2_SPI_STATUS 0x9e
> > +#define PAGE2_GPIO_L 0xa6
> > +#define PAGE2_GPIO_H 0xa7
> > +#define PS_GPIO9 BIT(1)
> > +#define PAGE2_IROM_CTRL 0xb0
> > +#define IROM_ENABLE 0xc0
> > +#define IROM_DISABLE 0x80
> > +#define PAGE2_SW_RESET 0xbc
> > +#define SPI_SW_RESET BIT(7)
> > +#define MPU_SW_RESET BIT(6)
> > +#define PAGE2_ENCTLSPI_WR 0xda
> > +#define PAGE2_I2C_BYPASS 0xea
> > +#define I2C_BYPASS_EN 0xd0
> > +#define PAGE3_SET_ADD 0xfe
> > +#define PAGE3_SET_VAL 0xff
> > +#define VDO_CTL_ADD 0x13
> > +#define VDO_DIS 0x18
> > +#define VDO_EN 0x1c
> > +#define PAGE4_REV_L 0xf0
> > +#define PAGE4_REV_H 0xf1
> > +#define PAGE4_CHIP_L 0xf2
> > +#define PAGE4_CHIP_H 0xf3
> > +
> > +/* Firmware */
> > +#define SPI_MAX_RETRY_CNT 8
> > +#define PS_FW_NAME "ps864x_fw.bin"
> > +
> > +#define FW_CHIP_ID_OFFSET 0
> > +#define FW_VERSION_OFFSET 2
> > +#define EDID_I2C_ADDR 0x50
> > +
> > +#define WRITE_STATUS_REG_CMD 0x01
> > +#define READ_STATUS_REG_CMD 0x05
> > +#define BUSY BIT(0)
> > +#define CLEAR_ALL_PROTECT 0x00
> > +#define BLK_PROTECT_BITS 0x0c
> > +#define STATUS_REG_PROTECT BIT(7)
> > +#define WRITE_ENABLE_CMD 0x06
> > +#define CHIP_ERASE_CMD 0xc7
> > +
> > +#define bridge_to_ps8640(e) container_of(e, struct ps8640, bridge)
> > +#define connector_to_ps8640(e) container_of(e, struct ps8640, connector)
>
> I'd prefer these to be static inline functions.
I'll update it next version.
Thanks
>
> > +
> > +struct ps8640_info {
> > + u8 family_id;
> > + u8 variant_id;
> > + u16 version;
> > +};
> > +
> > +struct ps8640 {
> > + struct drm_connector connector;
> > + struct drm_bridge bridge;
> > + struct edid *edid;
> > + struct mipi_dsi_device dsi;
> > + struct i2c_client *page[8];
> > + struct i2c_client *ddc_i2c;
> > + struct regulator_bulk_data supplies[2];
> > + struct drm_panel *panel;
> > + struct gpio_desc *gpio_rst_n;
> > + struct gpio_desc *gpio_slp_n;
> > + struct gpio_desc *gpio_mode_sel_n;
> > + bool enabled;
> > +
> > + /* firmware file info */
> > + bool in_fw_update;
> > + struct ps8640_info info;
> > +};
> > +
> > +static const u8 enc_ctrl_code[6] = {0xaa, 0x55, 0x50, 0x41, 0x52, 0x44};
> > +static const u8 hw_chip_id[4] = {0x00, 0x0a, 0x00, 0x30};
>
> Spaces after { and before }, please.
I'll fix them next version, thanks.
> > +
> > +static int ps8640_read(struct i2c_client *client, u8 reg, u8 *data,
> > + u16 data_len)
> > +{
> > + int ret;
> > + struct i2c_msg msgs[] = {
> > + {
> > + .addr = client->addr,
> > + .flags = 0,
> > + .len = 1,
> > + .buf = ®,
> > + },
> > + {
> > + .addr = client->addr,
> > + .flags = I2C_M_RD,
> > + .len = data_len,
> > + .buf = data,
> > + }
>
> Please indent properly here. This uses a weird mix of tabs and spaces,
> where it should be tabs only.
I'll fix it next version.
Thanks
>
> > + };
> > +
> > + ret = i2c_transfer(client->adapter, msgs, 2);
> > +
> > + if (ret == 2)
> > + return 0;
> > + if (ret < 0)
> > + return ret;
> > + else
> > + return -EIO;
> > +}
> > +
> > +static int ps8640_write_bytes(struct i2c_client *client, const u8 *data,
> > + u16 data_len)
> > +{
> > + int ret;
> > + struct i2c_msg msg;
> > +
> > + msg.addr = client->addr;
> > + msg.flags = 0;
> > + msg.len = data_len;
> > + msg.buf = (u8 *)data;
> > +
> > + ret = i2c_transfer(client->adapter, &msg, 1);
> > + if (ret == 1)
> > + return 0;
> > + if (ret < 0)
> > + return ret;
> > + else
> > + return -EIO;
> > +}
> > +
> > +static int ps8640_write_byte(struct i2c_client *client, u8 reg, u8 data)
> > +{
> > + u8 buf[] = {reg, data};
>
> Spaces after { and before }, please. There are a bunch more of those
> below, please fix those up as well.
I'll fix them next version.
Thanks
>
> > +
> > + return ps8640_write_bytes(client, buf, sizeof(buf));
> > +}
> > +
> > +static void ps8640_get_mcu_fw_version(struct ps8640 *ps_bridge)
> > +{
> > + struct i2c_client *client = ps_bridge->page[5];
> > + u8 fw_ver[2];
> > +
> > + ps8640_read(client, 0x4, fw_ver, 2);
>
> sizeof(fw_ver) perhaps and check for errors?
I'll fix it next version.
Thanks
>
> > + ps_bridge->info.version = (fw_ver[0] << 8) | fw_ver[1];
> > +
> > + DRM_INFO_ONCE("ps8640 rom fw version %d.%d\n", fw_ver[0], fw_ver[1]);
> > +}
> > +
> > +static int ps8640_bridge_enable(struct ps8640 *ps_bridge)
> > +{
> > + struct i2c_client *client = ps_bridge->page[3];
> > + u8 vdo_ctrl_buf[3] = {PAGE3_SET_ADD, VDO_CTL_ADD, VDO_EN};
> > +
> > + return ps8640_write_bytes(client, vdo_ctrl_buf, 3);
>
> sizeof(vdo_ctrl_buf)? There are more of these in a couple of places.
I'll fix it next version.
Thanks
>
> > +static void ps8640_post_disable(struct drm_bridge *bridge)
> > +{
> > + struct ps8640 *ps_bridge = bridge_to_ps8640(bridge);
> > + int err;
> > +
> > + if (ps_bridge->in_fw_update)
> > + return;
>
> I don't like how this is handled. Consider what happens if you are in
> the process of updating the firmware. The above code along with that in
> other parts of the driver will silently ignore all operations on the
> bridge during an update. I think these places should be updated to
> return an error code (-EAGAIN, -EBUSY or the like) or they should block
> all operations (perhaps via a mutex) until the firmware update is
> complete.
>
I'll add mutex when firmware update next version.
> > +static int ps8640_get_modes(struct drm_connector *connector)
> > +{
> > + struct ps8640 *ps_bridge = connector_to_ps8640(connector);
> > + struct device *dev = &ps_bridge->page[0]->dev;
> > + u8 *edid;
> > + int ret, num_modes = 0;
> > + bool power_off;
> > +
> > + if (ps_bridge->edid)
> > + return drm_add_edid_modes(connector, ps_bridge->edid);
> > +
> > + power_off = !ps_bridge->enabled;
> > + ps8640_pre_enable(&ps_bridge->bridge);
> > +
> > + edid = devm_kmalloc(dev, EDID_LENGTH, GFP_KERNEL);
> > + if (!edid) {
> > + DRM_ERROR("Failed to allocate EDID\n");
> > + return 0;
> > + }
> > +
> > + ret = ps8640_read(ps_bridge->ddc_i2c, 0, edid, EDID_LENGTH);
> > + if (ret)
> > + goto out;
>
> This should be using the standard EDID helpers.
I'll fix it next version.
Thanks
>
> > +/* Firmware Version is returned as Major.Minor.Build */
>
> No, it isn't. The below returns "x.y" (which I assume is "major.minor").
>
I'll fix it next version.
Thanks
> > +static ssize_t ps8640_fw_version_show(struct device *dev,
> > + struct device_attribute *attr, char *buf)
> > +{
> > + struct ps8640 *ps_bridge = dev_get_drvdata(dev);
> > + struct ps8640_info *info = &ps_bridge->info;
> > +
> > + return scnprintf(buf, PAGE_SIZE, "%u.%u\n", info->version >> 8,
> > + info->version & 0xff);
> > +}
> [...]
> > +static int ps8640_spi_send_cmd(struct ps8640 *ps_bridge, u8 *cmd, u8 cmd_len)
> > +{
> > + struct i2c_client *client = ps_bridge->page[2];
> > + u8 i, buf[3] = {PAGE2_SWSPI_LEN, cmd_len - 1, TRIGGER_NO_READBACK};
> > + int ret;
> > +
> > + ret = ps8640_write_byte(client, PAGE2_IROM_CTRL, IROM_ENABLE);
> > + if (ret)
> > + goto err;
> > +
> > + /* write command in write port */
> > + for (i = 0; i < cmd_len; i++) {
> > + ret = ps8640_write_byte(client, PAGE2_SWSPI_WDATA, cmd[i]);
> > + if (ret) {
> > + ps8640_write_byte(client, PAGE2_IROM_CTRL,
> > + IROM_DISABLE);
> > + goto err;
>
> Can't this simply be "goto err_irom_disable;"?
I'll fix it next version.
Thanks
>
> > + }
> > + }
> > +
> > + ret = ps8640_write_bytes(client, buf, 3);
> > + if (ret)
> > + goto err_irom_disable;
> > +
> > + ret = ps8640_write_byte(client, PAGE2_IROM_CTRL, IROM_DISABLE);
> > + if (ret)
> > + goto err;
> > +
> > + return 0;
> > +err_irom_disable:
> > + ps8640_write_byte(client, PAGE2_IROM_CTRL, IROM_DISABLE);
> > +err:
> > + dev_err(&client->dev, "send command err: %d\n", ret);
> > + return ret;
> > +}
> > +
> > +static int ps8640_wait_spi_ready(struct ps8640 *ps_bridge)
> > +{
> > + struct i2c_client *client = ps_bridge->page[2];
> > + u8 spi_rdy_st;
> > + ktime_t timeout;
> > +
> > + timeout = ktime_add_ms(ktime_get(), 200);
> > + for (;;) {
> > + ps8640_read(client, PAGE2_SPI_STATUS, &spi_rdy_st, 1);
> > + if ((spi_rdy_st & 0x0c) != 0x0c)
>
> Can we get symbolic names for 0x0c, please?
I'll fix it next version.
Thanks
>
> > + break;
> > +
> > + if (ktime_compare(ktime_get(), timeout) > 0) {
> > + dev_err(&client->dev, "wait spi ready timeout\n");
> > + return -EBUSY;
> > + }
> > +
> > + msleep(20);
> > + }
> > +
> > + return 0;
> > +}
> [...]
> > +static int ps8640_write_rom(struct ps8640 *ps_bridge, const struct firmware *fw)
> > +{
> > + struct i2c_client *client = ps_bridge->page[0];
> > + struct device *dev = &client->dev;
> > + struct i2c_client *client2 = ps_bridge->page[2];
> > + struct i2c_client *client7 = ps_bridge->page[7];
> > + unsigned int pos = 0;
>
> Make this size_t since you compare it to fw->size, which is size_t as
> well.
I'll fix it next version.
Thanks
>
> > + u8 buf[257], rom_page_id_buf[3];
> > + int ret;
> > + u16 cpy_len;
> > +
> > + ps8640_write_byte(client2, PAGE2_SPI_CFG3, I2C_TO_SPI_RESET);
> > + msleep(100);
> > + ps8640_write_byte(client2, PAGE2_SPI_CFG3, 0x00);
> > +
> > + for (pos = 0; pos < fw->size; pos += cpy_len) {
> > + rom_page_id_buf[0] = PAGE2_ROMADD_BYTE1;
> > + rom_page_id_buf[1] = pos >> 8;
> > + rom_page_id_buf[2] = pos >> 16;
> > + ret = ps8640_write_bytes(client2, rom_page_id_buf, 3);
> > + if (ret)
> > + goto error;
> > + cpy_len = fw->size >= 256 + pos ? 256 : fw->size - pos;
> > + buf[0] = 0;
> > + memcpy(buf + 1, fw->data + pos, cpy_len);
> > + ret = ps8640_write_bytes(client7, buf, cpy_len + 1);
> > + if (ret)
> > + goto error;
> > +
> > + dev_dbg(dev, "fw update completed %u / %zu bytes\n", pos,
> > + fw->size);
> > + }
> > + return 0;
> > +
> > +error:
> > + dev_err(dev, "failed write extenal flash, %d\n", ret);
>
> "external"
I'll fix it next version.
Thanks
>
> > + return ret;
> > +}
> > +
> > +static int ps8640_spi_normal_mode(struct ps8640 *ps_bridge)
> > +{
> > + u8 cmd[2];
> > + struct i2c_client *client = ps_bridge->page[2];
> > +
> > + /* Enable-Write-Status-Register */
> > + cmd[0] = WRITE_ENABLE_CMD;
> > + ps8640_spi_send_cmd(ps_bridge, cmd, 1);
> > +
> > + /* protect BPL/BP0/BP1 */
> > + cmd[0] = WRITE_STATUS_REG_CMD;
> > + cmd[1] = BLK_PROTECT_BITS | STATUS_REG_PROTECT;
> > + ps8640_spi_send_cmd(ps_bridge, cmd, 2);
> > +
> > + /* wait for SPI rom ready */
> > + ps8640_wait_rom_idle(ps_bridge);
> > +
> > + /* disable PS8640 mapping function */
> > + ps8640_write_byte(client, PAGE2_ENCTLSPI_WR, 0x00);
> > +
> > + gpiod_set_value(ps_bridge->gpio_mode_sel_n, 1);
> > + return 0;
> > +}
> > +
> > +static int ps8640_enter_bl(struct ps8640 *ps_bridge)
> > +{
> > + ps_bridge->in_fw_update = true;
>
> Besides my other comments on this, I think you'll need proper locking
> here, otherwise you might end up in a situation where you can still
> power off the chip during firmware update. Consider the case where you
> power off the chip, pass the in_fw_update check but then immediately
> trigger the firmware update via sysfs and start updating while the chip
> is being shut down.
>
I'll fix it next version. I'll add mutex whole firmware updating to
protect.
Thanks
> > + return ps8640_spi_dl_mode(ps_bridge);
> > +}
> > +
> > +static void ps8640_exit_bl(struct ps8640 *ps_bridge, const struct firmware *fw)
> > +{
> > + ps8640_spi_normal_mode(ps_bridge);
> > + ps_bridge->in_fw_update = false;
> > +}
> > +
> > +static int ps8640_load_fw(struct ps8640 *ps_bridge, const struct firmware *fw)
> > +{
> > + struct i2c_client *client = ps_bridge->page[0];
> > + struct device *dev = &client->dev;
> > + int ret;
> > + bool ps8640_status_backup = ps_bridge->enabled;
> > +
> > + ret = ps8640_validate_firmware(ps_bridge, fw);
> > + if (ret)
> > + return ret;
> > +
> > + if (!ps_bridge->in_fw_update) {
> > + if (!ps8640_status_backup)
> > + ps8640_pre_enable(&ps_bridge->bridge);
> > +
> > + ret = ps8640_enter_bl(ps_bridge);
> > + if (ret)
> > + goto exit;
> > + }
> > +
> > + ret = ps8640_rom_prepare(ps_bridge);
> > + if (ret)
> > + goto exit;
> > +
> > + ret = ps8640_write_rom(ps_bridge, fw);
> > +
> > +exit:
> > + if (ret)
> > + dev_err(dev, "Failed to load firmware, %d\n", ret);
> > +
> > + ps8640_exit_bl(ps_bridge, fw);
> > + if (!ps8640_status_backup)
> > + ps8640_post_disable(&ps_bridge->bridge);
> > + return ret;
>
> Taking a mutex around all of this code might be the easiest way to
> achieve this.
I'll fix it next version. I'll add mutex when firmware updating
Thanks
>
> > +}
> > +
> > +static ssize_t ps8640_update_fw_store(struct device *dev,
> > + struct device_attribute *attr,
> > + const char *buf, size_t count)
> > +{
> > + struct i2c_client *client = to_i2c_client(dev);
> > + struct ps8640 *ps_bridge = i2c_get_clientdata(client);
> > + const struct firmware *fw;
> > + int error;
> > +
> > + error = request_firmware(&fw, PS_FW_NAME, dev);
> > + if (error) {
> > + dev_err(dev, "Unable to open firmware %s: %d\n",
> > + PS_FW_NAME, error);
> > + return error;
> > + }
> > +
> > + error = ps8640_load_fw(ps_bridge, fw);
> > + if (error)
> > + dev_err(dev, "The firmware update failed(%d)\n", error);
> > + else
> > + dev_info(dev, "The firmware update succeeded\n");
> > +
> > + release_firmware(fw);
> > + return error ? error : count;
> > +}
>
> This sysfs interface is somewhat unintuitive because it triggers no
> matter what you write to the file. I find it also a little unusual that
> you would trigger a firmware update through sysfs, but then go through
> the request_firmware() to obtain it. Is this a common method, or do
> other drivers do something different?
>
Thanks, i think it is a common method.
Other drivers are same ex. the drivers\input\mouse\elan_i2c_core.c
> > +static int ps8640_probe(struct i2c_client *client,
> > + const struct i2c_device_id *id)
> > +{
> > + struct device *dev = &client->dev;
> > + struct ps8640 *ps_bridge;
> > + struct device_node *np = dev->of_node;
> > + struct device_node *port, *out_ep;
> > + struct device_node *panel_node = NULL;
> > + int i, ret;
>
> i could be unsigned.
I'll fix it next version.
Thanks
>
> > +
> > + ps_bridge = devm_kzalloc(dev, sizeof(*ps_bridge), GFP_KERNEL);
> > + if (!ps_bridge)
> > + return -ENOMEM;
> > +
> > + /* port at 1 is ps8640 output port */
> > + port = of_graph_get_port_by_id(np, 1);
> > + if (port) {
> > + out_ep = of_get_child_by_name(port, "endpoint");
> > + of_node_put(port);
> > + if (out_ep) {
> > + panel_node = of_graph_get_remote_port_parent(out_ep);
> > + of_node_put(out_ep);
> > + }
> > + }
> > + if (panel_node) {
> > + ps_bridge->panel = of_drm_find_panel(panel_node);
> > + of_node_put(panel_node);
> > + if (!ps_bridge->panel)
> > + return -EPROBE_DEFER;
> > + }
> > +
> > + ps_bridge->supplies[0].supply = "vdd33";
> > + ps_bridge->supplies[1].supply = "vdd12";
> > + ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ps_bridge->supplies),
> > + ps_bridge->supplies);
> > + if (ret) {
> > + dev_info(dev, "failed to get regulators: %d\n", ret);
> > + return ret;
> > + }
> > +
> > + ps_bridge->gpio_mode_sel_n = devm_gpiod_get(&client->dev, "mode-sel",
> > + GPIOD_OUT_HIGH);
>
> This GPIO is used to enable programming mode. Perhaps it should be made
> optional, and the programming mode refuse to run if it isn't specified?
I'll fix it next version.
Thanks
>
> > + if (IS_ERR(ps_bridge->gpio_mode_sel_n)) {
> > + ret = PTR_ERR(ps_bridge->gpio_mode_sel_n);
> > + dev_err(dev, "cannot get mode-sel %d\n", ret);
> > + return ret;
> > + }
> > +
> > + ps_bridge->gpio_slp_n = devm_gpiod_get(&client->dev, "sleep",
> > + GPIOD_OUT_LOW);
> > + if (IS_ERR(ps_bridge->gpio_slp_n)) {
> > + ret = PTR_ERR(ps_bridge->gpio_slp_n);
> > + dev_err(dev, "cannot get sleep: %d\n", ret);
> > + return ret;
> > + }
> > +
> > + /*
> > + * Request the reset pin low to avoid the bridge being
> > + * initialized prematurely
> > + */
> > + ps_bridge->gpio_rst_n = devm_gpiod_get(&client->dev, "reset",
> > + GPIOD_OUT_LOW);
> > + if (IS_ERR(ps_bridge->gpio_rst_n)) {
> > + ret = PTR_ERR(ps_bridge->gpio_rst_n);
> > + dev_err(dev, "cannot get reset: %d\n", ret);
> > + return ret;
> > + }
> > +
> > + ps_bridge->bridge.funcs = &ps8640_bridge_funcs;
> > + ps_bridge->bridge.of_node = dev->of_node;
> > + ret = drm_bridge_add(&ps_bridge->bridge);
>
> Perhaps postpone the call to drm_bridge_add() until everything has been
> properly set up? That way you don't have to undo it again if something
> goes wrong in the more likely places.
I'll fix it next version.
Thanks
>
> > + if (ret) {
> > + dev_err(dev, "Failed to add bridge: %d\n", ret);
> > + return ret;
> > + }
> > +
> > + ps_bridge->page[0] = client;
> > + ps_bridge->ddc_i2c = i2c_new_dummy(client->adapter, EDID_I2C_ADDR);
> > + if (!ps_bridge->ddc_i2c) {
> > + dev_err(dev, "failed ddc_i2c dummy device, address%02x\n",
> > + EDID_I2C_ADDR);
> > + ret = -EBUSY;
> > + goto exit_ddc_i2c_dummy;
> > + }
> > + /*
> > + * ps8640 uses multiple addresses, use dummy devices for them
> > + * 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
> > + */
> > + for (i = 1; i < 8; i++) {
> > + ps_bridge->page[i] = i2c_new_dummy(client->adapter,
> > + client->addr + i);
> > + if (!ps_bridge->page[i]) {
> > + dev_err(dev, "failed i2c dummy device, address%02x\n",
> > + client->addr + i);
> > + ret = -EBUSY;
> > + goto exit_dummy;
> > + }
> > + }
> > + i2c_set_clientdata(client, ps_bridge);
> > +
> > + ret = sysfs_create_group(&client->dev.kobj, &ps8640_attr_group);
> > + if (ret) {
> > + dev_err(dev, "failed to create sysfs entries: %d\n", ret);
> > + goto exit_dummy;
> > + }
> > +
> > + ret = devm_add_action(dev, ps8640_remove_sysfs_group, ps_bridge);
> > + if (ret) {
> > + dev_err(dev, "failed to add sysfs cleanup action: %d\n", ret);
> > + goto exit_remove_sysfs;
> > + }
> > + return 0;
> > +
> > +exit_remove_sysfs:
> > + sysfs_remove_group(&ps_bridge->page[0]->dev.kobj, &ps8640_attr_group);
> > +exit_dummy:
> > + for (i = 1; i < 8; i++)
> > + if (ps_bridge->page[i])
> > + i2c_unregister_device(ps_bridge->page[i]);
>
> Might be better to make this into something like:
>
> while (--i)
> i2c_unregister_device(ps_bridge->page[i]);
>
> That way you can omit the check for valid page because you only
> unregister the ones you've successfully registered before.
>
Got it, I'll fix it next version.
Thanks
> > + i2c_unregister_device(ps_bridge->ddc_i2c);
> > +exit_ddc_i2c_dummy:
> > + drm_bridge_remove(&ps_bridge->bridge);
> > + return ret;
> > +}
> > +
> > +static int ps8640_remove(struct i2c_client *client)
> > +{
> > + struct ps8640 *ps_bridge = i2c_get_clientdata(client);
> > + int i;
> > +
> > + for (i = 1; i < 8; i++)
> > + i2c_unregister_device(ps_bridge->page[i]);
> > +
> > + i2c_unregister_device(ps_bridge->ddc_i2c);
> > + drm_bridge_remove(&ps_bridge->bridge);
> > +
> > + return 0;
> > +}
>
> The ordering here should be the reverse of that in ->probe().
>
I'll fix it next version.
Thanks
> > +
> > +static const struct i2c_device_id ps8640_i2c_table[] = {
> > + {"parade,ps8640", 0},
> > + {},
>
> Spaces after { and before }. Also is this really correct? I thought for
> I2C device IDs we didn't need a vendor prefix.
>
I refer other i2c device, they also contain the vendor prefix.
> Thierry
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