[PATCH v10 2/2] drm/bridge: Add I2C based driver for ps8640 bridge
Philipp Zabel
p.zabel at pengutronix.de
Fri Feb 19 09:12:25 UTC 2016
Am Freitag, den 19.02.2016, 16:31 +0800 schrieb Jitao Shi:
> This patch adds drm_bridge driver for parade DSI to eDP bridge chip.
>
> Signed-off-by: Jitao Shi <jitao.shi at mediatek.com>
> ---
> Changes since v9:
> - replace dev_kmalloc with devm_kmalloc in ps8640_get_modes
> - remove ps_bridge->dsi = devm_kzalloc(dev, sizeof(struct mipi_dsi_device),
> GFP_KERNEL);
> - fix wrong condition in ps8640_validate_firmware()
>
> The following patches are needed to support dsi host through none dsi bus:
>
> https://patchwork.kernel.org/patch/8289181/ ("drm/dsi: check for CONFIG_OF when defining")
> https://patchwork.kernel.org/patch/8289051/ ("drm/dsi: Use mipi_dsi_device_register_full for DSI device")
> https://patchwork.kernel.org/patch/8289081/ ("drm/dsi: Try to match non-DT DSI devices")
> https://patchwork.kernel.org/patch/8289121/ ("drm/dsi: Add routine to unregister a DSI device")
> https://patchwork.kernel.org/patch/8289091/ ("drm/dsi: Get DSI host by DT device node")
> ---
> drivers/gpu/drm/bridge/Kconfig | 11 +
> drivers/gpu/drm/bridge/Makefile | 1 +
> drivers/gpu/drm/bridge/parade-ps8640.c | 1057 ++++++++++++++++++++++++++++++++
> 3 files changed, 1069 insertions(+)
> create mode 100644 drivers/gpu/drm/bridge/parade-ps8640.c
>
> diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
> index 27e2022..b4edd8c 100644
> --- a/drivers/gpu/drm/bridge/Kconfig
> +++ b/drivers/gpu/drm/bridge/Kconfig
> @@ -40,4 +40,15 @@ config DRM_PARADE_PS8622
> ---help---
> Parade eDP-LVDS bridge chip driver.
>
> +config DRM_PARADE_PS8640
> + tristate "Parade PS8640 MIPI DSI to eDP Converter"
> + depends on OF && I2C
> + select DRM_KMS_HELPER
> + select DRM_MIPI_DSI
> + select DRM_PANEL
> + ---help---
> + Choose this option if you have PS8640 for display
> + The PS8640 is a high-performance and low-power
> + MIPI DSI to eDP converter
> +
> endmenu
> diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
> index f13c33d..fbe38dc 100644
> --- a/drivers/gpu/drm/bridge/Makefile
> +++ b/drivers/gpu/drm/bridge/Makefile
> @@ -4,3 +4,4 @@ obj-$(CONFIG_DRM_DW_HDMI) += dw-hdmi.o
> obj-$(CONFIG_DRM_DW_HDMI_AHB_AUDIO) += dw-hdmi-ahb-audio.o
> obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o
> obj-$(CONFIG_DRM_PARADE_PS8622) += parade-ps8622.o
> +obj-$(CONFIG_DRM_PARADE_PS8640) += parade-ps8640.o
> diff --git a/drivers/gpu/drm/bridge/parade-ps8640.c b/drivers/gpu/drm/bridge/parade-ps8640.c
> new file mode 100644
> index 0000000..5f27548
> --- /dev/null
> +++ b/drivers/gpu/drm/bridge/parade-ps8640.c
> @@ -0,0 +1,1057 @@
> +/*
> + * Copyright (c) 2014 MediaTek Inc.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#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_REST 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 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)
> +
> +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 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,
> + }
> + };
> +
> + 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, u8 *data,
> + u16 data_len)
> +{
> + int ret;
> + struct i2c_msg msg;
> +
> + msg.addr = client->addr;
> + msg.flags = 0;
> + msg.len = data_len;
> + msg.buf = 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)
> +{
> + int ret;
> + struct i2c_msg msg;
> + u8 buf[] = {reg, data};
> +
> + msg.addr = client->addr;
> + msg.flags = 0;
> + msg.len = sizeof(buf);
> + msg.buf = buf;
> +
> + ret = i2c_transfer(client->adapter, &msg, 1);
> + if (ret == 1)
> + return 0;
> + if (ret < 0)
> + return ret;
> + else
> + return -EIO;
> +}
> +
> +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);
> + 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);
> +}
> +
> +static int ps8640_bridge_disable(struct ps8640 *ps_bridge)
> +{
> + struct i2c_client *client = ps_bridge->page[3];
> + u8 vdo_ctrl_buf[3] = {PAGE3_SET_ADD, VDO_CTL_ADD, VDO_DIS};
> +
> + return ps8640_write_bytes(client, vdo_ctrl_buf, 3);
> +}
> +
> +static void ps8640_pre_enable(struct drm_bridge *bridge)
> +{
> + struct ps8640 *ps_bridge = bridge_to_ps8640(bridge);
> + struct i2c_client *client = ps_bridge->page[2];
> + int err, retry_cnt = 0;
> + u8 set_vdo_done;
> +
> + if (ps_bridge->in_fw_update)
> + return;
> +
> + if (ps_bridge->enabled)
> + return;
> +
> + err = drm_panel_prepare(ps_bridge->panel);
> + if (err < 0) {
> + DRM_ERROR("failed to prepare panel: %d\n", err);
> + return;
> + }
> +
> + gpiod_set_value(ps_bridge->gpio_slp_n, 1);
Is this part:
> + gpiod_set_value(ps_bridge->gpio_rst_n, 0);
> +
> + err = regulator_bulk_enable(ARRAY_SIZE(ps_bridge->supplies),
> + ps_bridge->supplies);
> + if (err < 0) {
> + DRM_ERROR("cannot enable regulators %d\n", err);
> + goto err_panel_unprepare;
> + }
> +
> + usleep_range(500, 700);
> + gpiod_set_value(ps_bridge->gpio_rst_n, 1);
.. until here an assertion of the reset for 500 µs plus whatever the
regulator delay is (if any)? It looks like the reset actually is active
low. If so, I think this code should rather be:
gpiod_set_value(ps_bridge->gpio_rst_n, 1);
regulator_bulk_enable();
usleep_range();
gpiod_set_value(ps_bridge->gpio_rst_n, 0);
And the device tree should contain a reset-gpios property with the
GPIO_ACTIVE_LOW flag set.
Same goes for sleep GPIO, if it is active low, too.
best regards
Philipp
More information about the dri-devel
mailing list