drm/panel: s6e63m0: Break out SPI transport

This panel can be accessed using both SPI and DSI.

To make it possible to probe and use the device also from
a DSI bus, first break out the SPI support to its own file.

Since all the panel driver does is write DCS commands to
the panel, we pass a DCS write function to probe()
from each subdriver.

We make the Kconfig entry for SPI mode default so all
current users will continue to work.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Stephan Gerhold <stephan@gerhold.net>
Cc: Paweł Chmiel <pawel.mikolaj.chmiel@gmail.com>
Acked-by: Paul Cercueil <paul@crapouillou.net>
Link: https://patchwork.freedesktop.org/patch/384873/

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index 8d97d07..f8d61e6 100644 (file)
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -324,13 +324,22 @@ config DRM_PANEL_SAMSUNG_S6E63J0X03
        select VIDEOMODE_HELPERS
 
 config DRM_PANEL_SAMSUNG_S6E63M0
-       tristate "Samsung S6E63M0 RGB/SPI panel"
+       tristate "Samsung S6E63M0 RGB panel"
        depends on OF
-       depends on SPI
        depends on BACKLIGHT_CLASS_DEVICE
        help
          Say Y here if you want to enable support for Samsung S6E63M0
-         AMOLED LCD panel.
+         AMOLED LCD panel. This panel can be accessed using SPI or
+         DSI.
+
+config DRM_PANEL_SAMSUNG_S6E63M0_SPI
+       tristate "Samsung S6E63M0 RGB SPI interface"
+       depends on SPI
+       depends on DRM_PANEL_SAMSUNG_S6E63M0
+       default DRM_PANEL_SAMSUNG_S6E63M0
+       help
+         Say Y here if you want to be able to access the Samsung
+         S6E63M0 panel using SPI.
 
 config DRM_PANEL_SAMSUNG_S6E88A0_AMS452EF01
        tristate "Samsung AMS452EF01 panel with S6E88A0 DSI video mode controller"

diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index 15a4e77..63f53bd 100644 (file)
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -34,6 +34,7 @@ obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6D16D0) += panel-samsung-s6d16d0.o
 obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E3HA2) += panel-samsung-s6e3ha2.o
 obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E63J0X03) += panel-samsung-s6e63j0x03.o
 obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E63M0) += panel-samsung-s6e63m0.o
+obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E63M0_SPI) += panel-samsung-s6e63m0-spi.o
 obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E88A0_AMS452EF01) += panel-samsung-s6e88a0-ams452ef01.o
 obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E8AA0) += panel-samsung-s6e8aa0.o
 obj-$(CONFIG_DRM_PANEL_SEIKO_43WVF1G) += panel-seiko-43wvf1g.o

diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e63m0-spi.c b/drivers/gpu/drm/panel/panel-samsung-s6e63m0-spi.c
new file mode 100644 (file)
index 0000000..4082fbd
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-samsung-s6e63m0-spi.c
@@ -0,0 +1,89 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+#include <linux/delay.h>
+
+#include <drm/drm_print.h>
+
+#include "panel-samsung-s6e63m0.h"
+
+#define DATA_MASK      0x100
+
+static int s6e63m0_spi_write_word(struct device *dev, u16 data)
+{
+       struct spi_device *spi = to_spi_device(dev);
+       struct spi_transfer xfer = {
+               .len    = 2,
+               .tx_buf = &data,
+       };
+       struct spi_message msg;
+
+       spi_message_init(&msg);
+       spi_message_add_tail(&xfer, &msg);
+
+       return spi_sync(spi, &msg);
+}
+
+static int s6e63m0_spi_dcs_write(struct device *dev, const u8 *data, size_t len)
+{
+       int ret = 0;
+
+       DRM_DEV_DEBUG(dev, "SPI writing dcs seq: %*ph\n", (int)len, data);
+       ret = s6e63m0_spi_write_word(dev, *data);
+
+       while (!ret && --len) {
+               ++data;
+               ret = s6e63m0_spi_write_word(dev, *data | DATA_MASK);
+       }
+
+       if (ret) {
+               DRM_DEV_ERROR(dev, "SPI error %d writing dcs seq: %*ph\n", ret,
+                             (int)len, data);
+       }
+
+       usleep_range(300, 310);
+
+       return ret;
+}
+
+static int s6e63m0_spi_probe(struct spi_device *spi)
+{
+       struct device *dev = &spi->dev;
+       int ret;
+
+       spi->bits_per_word = 9;
+       spi->mode = SPI_MODE_3;
+       ret = spi_setup(spi);
+       if (ret < 0) {
+               DRM_DEV_ERROR(dev, "spi setup failed.\n");
+               return ret;
+       }
+       return s6e63m0_probe(dev, s6e63m0_spi_dcs_write);
+}
+
+static int s6e63m0_spi_remove(struct spi_device *spi)
+{
+       return s6e63m0_remove(&spi->dev);
+}
+
+static const struct of_device_id s6e63m0_spi_of_match[] = {
+       { .compatible = "samsung,s6e63m0" },
+       { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, s6e63m0_spi_of_match);
+
+static struct spi_driver s6e63m0_spi_driver = {
+       .probe                  = s6e63m0_spi_probe,
+       .remove                 = s6e63m0_spi_remove,
+       .driver                 = {
+               .name           = "panel-samsung-s6e63m0",
+               .of_match_table = s6e63m0_spi_of_match,
+       },
+};
+module_spi_driver(s6e63m0_spi_driver);
+
+MODULE_AUTHOR("Paweł Chmiel <pawel.mikolaj.chmiel@gmail.com>");
+MODULE_DESCRIPTION("s6e63m0 LCD SPI Driver");
+MODULE_LICENSE("GPL v2");

diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e63m0.c b/drivers/gpu/drm/panel/panel-samsung-s6e63m0.c
index 2cc772f..64d9520 100644 (file)
--- a/drivers/gpu/drm/panel/panel-samsung-s6e63m0.c
+++ b/drivers/gpu/drm/panel/panel-samsung-s6e63m0.c
@@ -16,10 +16,11 @@
 #include <linux/gpio/consumer.h>
 #include <linux/module.h>
 #include <linux/regulator/consumer.h>
-#include <linux/spi/spi.h>
 
 #include <video/mipi_display.h>
 
+#include "panel-samsung-s6e63m0.h"
+
 /* Manufacturer Command Set */
 #define MCS_ELVSS_ON                0xb1
 #define MCS_MIECTL1                0xc0
@@ -33,8 +34,6 @@
 #define NUM_GAMMA_LEVELS             11
 #define GAMMA_TABLE_COUNT           23
 
-#define DATA_MASK                                       0x100
-
 #define MAX_BRIGHTNESS              (NUM_GAMMA_LEVELS - 1)
 
 /* array of gamma tables for gamma value 2.2 */
@@ -87,6 +86,7 @@ static u8 const s6e63m0_gamma_22[NUM_GAMMA_LEVELS][GAMMA_TABLE_COUNT] = {
 
 struct s6e63m0 {
        struct device *dev;
+       int (*dcs_write)(struct device *dev, const u8 *data, size_t len);
        struct drm_panel panel;
        struct backlight_device *bl_dev;
 
@@ -134,42 +134,12 @@ static int s6e63m0_clear_error(struct s6e63m0 *ctx)
        return ret;
 }
 
-static int s6e63m0_spi_write_word(struct s6e63m0 *ctx, u16 data)
-{
-       struct spi_device *spi = to_spi_device(ctx->dev);
-       struct spi_transfer xfer = {
-               .len    = 2,
-               .tx_buf = &data,
-       };
-       struct spi_message msg;
-
-       spi_message_init(&msg);
-       spi_message_add_tail(&xfer, &msg);
-
-       return spi_sync(spi, &msg);
-}
-
 static void s6e63m0_dcs_write(struct s6e63m0 *ctx, const u8 *data, size_t len)
 {
-       int ret = 0;
-
        if (ctx->error < 0 || len == 0)
                return;
 
-       dev_dbg(ctx->dev, "writing dcs seq: %*ph\n", (int)len, data);
-       ret = s6e63m0_spi_write_word(ctx, *data);
-
-       while (!ret && --len) {
-               ++data;
-               ret = s6e63m0_spi_write_word(ctx, *data | DATA_MASK);
-       }
-
-       if (ret) {
-               dev_err(ctx->dev, "error %d writing dcs seq: %*ph\n", ret, (int)len, data);
-               ctx->error = ret;
-       }
-
-       usleep_range(300, 310);
+       ctx->error = ctx->dcs_write(ctx->dev, data, len);
 }
 
 #define s6e63m0_dcs_write_seq_static(ctx, seq ...) \
@@ -429,9 +399,9 @@ static int s6e63m0_backlight_register(struct s6e63m0 *ctx)
        return ret;
 }
 
-static int s6e63m0_probe(struct spi_device *spi)
+int s6e63m0_probe(struct device *dev,
+                 int (*dcs_write)(struct device *dev, const u8 *data, size_t len))
 {
-       struct device *dev = &spi->dev;
        struct s6e63m0 *ctx;
        int ret;
 
@@ -439,7 +409,8 @@ static int s6e63m0_probe(struct spi_device *spi)
        if (!ctx)
                return -ENOMEM;
 
-       spi_set_drvdata(spi, ctx);
+       ctx->dcs_write = dcs_write;
+       dev_set_drvdata(dev, ctx);
 
        ctx->dev = dev;
        ctx->enabled = false;
@@ -460,14 +431,6 @@ static int s6e63m0_probe(struct spi_device *spi)
                return PTR_ERR(ctx->reset_gpio);
        }
 
-       spi->bits_per_word = 9;
-       spi->mode = SPI_MODE_3;
-       ret = spi_setup(spi);
-       if (ret < 0) {
-               dev_err(dev, "spi setup failed.\n");
-               return ret;
-       }
-
        drm_panel_init(&ctx->panel, dev, &s6e63m0_drm_funcs,
                       DRM_MODE_CONNECTOR_DPI);
 
@@ -479,32 +442,14 @@ static int s6e63m0_probe(struct spi_device *spi)
 
        return 0;
 }
+EXPORT_SYMBOL_GPL(s6e63m0_probe);
 
-static int s6e63m0_remove(struct spi_device *spi)
+int s6e63m0_remove(struct device *dev)
 {
-       struct s6e63m0 *ctx = spi_get_drvdata(spi);
+       struct s6e63m0 *ctx = dev_get_drvdata(dev);
 
        drm_panel_remove(&ctx->panel);
 
        return 0;
 }
-
-static const struct of_device_id s6e63m0_of_match[] = {
-       { .compatible = "samsung,s6e63m0" },
-       { /* sentinel */ }
-};
-MODULE_DEVICE_TABLE(of, s6e63m0_of_match);
-
-static struct spi_driver s6e63m0_driver = {
-       .probe                  = s6e63m0_probe,
-       .remove                 = s6e63m0_remove,
-       .driver                 = {
-               .name           = "panel-samsung-s6e63m0",
-               .of_match_table = s6e63m0_of_match,
-       },
-};
-module_spi_driver(s6e63m0_driver);
-
-MODULE_AUTHOR("Paweł Chmiel <pawel.mikolaj.chmiel@gmail.com>");
-MODULE_DESCRIPTION("s6e63m0 LCD Driver");
-MODULE_LICENSE("GPL v2");
+EXPORT_SYMBOL_GPL(s6e63m0_remove);

diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e63m0.h b/drivers/gpu/drm/panel/panel-samsung-s6e63m0.h
new file mode 100644 (file)
index 0000000..44e31f3
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-samsung-s6e63m0.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _PANEL_SAMSUNG_S6E63M0_H
+#define _PANEL_SAMSUNG_S6E63M0_H
+
+int s6e63m0_probe(struct device *dev,
+                 int (*dcs_write)(struct device *dev, const u8 *data, size_t len));
+int s6e63m0_remove(struct device *dev);
+
+#endif /* _PANEL_SAMSUNG_S6E63M0_H */