[PATCH v1 5/5] tinydrm: add winstar wg160160 driver
Sam Ravnborg
sam at ravnborg.org
Thu Aug 2 19:45:36 UTC 2018
Add driver for the winstar wg160160 display.
The driver utilises pardata-dbi that
again utilise the pardata subsystem.
Signed-off-by: Sam Ravnborg <sam at ravnborg.org>
---
MAINTAINERS | 5 +
drivers/gpu/drm/tinydrm/Kconfig | 10 ++
drivers/gpu/drm/tinydrm/Makefile | 1 +
drivers/gpu/drm/tinydrm/wg160160.c | 298 +++++++++++++++++++++++++++++++++++++
4 files changed, 314 insertions(+)
create mode 100644 drivers/gpu/drm/tinydrm/wg160160.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 4ba7ff7c3e46..d77e53041395 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15501,6 +15501,11 @@ L: linux-watchdog at vger.kernel.org
S: Maintained
F: drivers/watchdog/ebc-c384_wdt.c
+WINSTAR WG160160 DRIVER
+M: Sam Ravnborg <sam at ravnborg.org>
+S: Maintained
+F: drivers/gpu/drm/tinydrm/wg160160.c
+
WINSYSTEMS WS16C48 GPIO DRIVER
M: William Breathitt Gray <vilhelm.gray at gmail.com>
L: linux-gpio at vger.kernel.org
diff --git a/drivers/gpu/drm/tinydrm/Kconfig b/drivers/gpu/drm/tinydrm/Kconfig
index 435de2f8d8f5..40315680c0bc 100644
--- a/drivers/gpu/drm/tinydrm/Kconfig
+++ b/drivers/gpu/drm/tinydrm/Kconfig
@@ -65,3 +65,13 @@ config TINYDRM_ST7735R
* JD-T18003-T01 1.8" 128x160 TFT
If M is selected the module will be called st7735r.
+
+config TINYDRM_WG160160
+ tristate "DRM support for Winstar WG160160"
+ depends on DRM_TINYDRM && PARDATA
+ select TINYDRM_PARDATA_DBI
+ help
+ DRM driver for Winstar WG160106.
+ See https://www.winstar.com.tw/products/graphic-lcd-display-module/lcd-graphics.html
+
+ If M is selected the module will be named wg160160.
diff --git a/drivers/gpu/drm/tinydrm/Makefile b/drivers/gpu/drm/tinydrm/Makefile
index 0b52df08b0a4..849891fe40cb 100644
--- a/drivers/gpu/drm/tinydrm/Makefile
+++ b/drivers/gpu/drm/tinydrm/Makefile
@@ -10,3 +10,4 @@ obj-$(CONFIG_TINYDRM_MI0283QT) += mi0283qt.o
obj-$(CONFIG_TINYDRM_REPAPER) += repaper.o
obj-$(CONFIG_TINYDRM_ST7586) += st7586.o
obj-$(CONFIG_TINYDRM_ST7735R) += st7735r.o
+obj-$(CONFIG_TINYDRM_WG160160) += wg160160.o
diff --git a/drivers/gpu/drm/tinydrm/wg160160.c b/drivers/gpu/drm/tinydrm/wg160160.c
new file mode 100644
index 000000000000..5477c8ed5599
--- /dev/null
+++ b/drivers/gpu/drm/tinydrm/wg160160.c
@@ -0,0 +1,298 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * DRM driver for Winstar WG160160 panels
+ *
+ * Copyright 2018 Sam Ravnborg <sam at ravnborg.org>
+ *
+ */
+
+#include <linux/gpio/consumer.h>
+#include <linux/backlight.h>
+#include <linux/property.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/tinydrm/tinydrm-helpers.h>
+#include <drm/tinydrm/pardata-dbi.h>
+#include <drm/drm_fb_helper.h>
+
+#define WG160160_MODE_REG 0x00
+#define MODE_GRAPHIC_DISP_OFF 0x12
+#define MODE_GRAPHIC_DISP_ON 0x32
+
+#define WG160160_PITCH_REG 0x01
+#define WG160160_WIDTH_REG 0x02
+#define WG160160_DUTY_REG 0x03
+#define WG160160_CURSORPOS_REG 0x04
+#define WG160160_ADDRSL_REG 0x08 /* Start lower address */
+#define WG160160_ADDRSU_REG 0x09 /* Start upper address */
+#define WG160160_WRITE_REG 0x0c /* Write byte, inc cursor */
+#define WG160160_READ_REG 0x0d /* Read byte, inc cursor */
+
+#define WG160160_BUSY_MASK 0x80
+#define BUSY_ACTIVE 1
+#define BUSY_INACTIVE 0
+
+/**
+ * busy_status -read status of busy flag
+ *
+ * @pdd: pardata data
+ *
+ * returns: true if busy, false if not
+ */
+static bool busy_status(struct pardata_data *pdd)
+{
+ int data;
+
+ gpiod_set_value_cansleep(pdd->bus->pin_rs, 1);
+ gpiod_set_value_cansleep(pdd->bus->pin_readwrite, 1);
+ gpiod_set_value_cansleep(pdd->pin_cs, 0);
+ /* min 90 nsec from cs/rs/rw to e */
+ udelay(1);
+ gpiod_set_value_cansleep(pdd->bus->pin_enable, 1);
+ /* data setup time 220 ns*/
+ udelay(2);
+
+ data = gpiod_get_value(pdd->bus->data_pins->desc[PIN_DB7]);
+
+ gpiod_set_value_cansleep(pdd->bus->pin_enable, 0);
+ /* data hold time 20 ns */
+ udelay(1);
+ gpiod_set_value_cansleep(pdd->pin_cs, 1);
+
+ return data == 1;
+}
+
+/**
+ * wait_busy - wait until controller is no longer busy
+ *
+ * Logs an ERROR once if we fail to see a not BUSY condition
+ *
+ * @pdd: pardata_data
+ */
+static void wait_busy(struct pardata_data *pdd)
+{
+ int i;
+
+ i = 0;
+
+ while (busy_status(pdd) && i++ < 10)
+ udelay(1);
+
+ if (i >= 10)
+ DRM_DEV_ERROR_RATELIMITED(&pdd->pddev->dev,
+ "Timeout waiting for BUSY=0\n");
+}
+
+/**
+ * write_reg - Write instruction on parallel bus to controller
+ *
+ * Check BUSY flag and write instruction
+ *
+ * @pdd: pardata data
+ * @reg: The register to write
+ * @value: The value of the register
+ *
+ * Returns:
+ * Zero on success, negative error code on failure
+ */
+int write_reg(struct pardata_data *pdd, unsigned int reg, unsigned int value)
+{
+ int ins[PIN_NUM];
+ int val[PIN_NUM];
+ int i;
+
+ for (i = 0; i < PIN_NUM; i++)
+ ins[PIN_DB0 + i] = !!BIT(reg);
+
+ for (i = 0; i < PIN_NUM; i++)
+ val[PIN_DB0 + i] = !!(value & BIT(i));
+
+ gpiod_set_value_cansleep(pdd->bus->pin_rs, 1);
+ gpiod_set_array_value_cansleep(PIN_NUM, pdd->bus->data_pins->desc, ins);
+ wait_busy(pdd);
+ pardata_strobe_write(pdd);
+
+ gpiod_set_value_cansleep(pdd->bus->pin_rs, 0);
+ gpiod_set_array_value_cansleep(PIN_NUM, pdd->bus->data_pins->desc, val);
+ wait_busy(pdd);
+ pardata_strobe_write(pdd);
+
+ return 0;
+}
+
+/**
+ * write_buf - write buffer on parallel bus to controller
+ *
+ * @pdd: pardata data
+ * @offset: offset into display RAM
+ * @data: pointer to data to write
+ * @len: number of bytes to write
+ *
+ * Returns:
+ * Zero on success, negative error code on failure
+ */
+int write_buf(struct pardata_data *pdd, u8 offset, u8 *data, size_t len)
+{
+ int ins[PIN_NUM];
+ int val[PIN_NUM];
+ int bit;
+ int i;
+
+ /* Setup address */
+ write_reg(pdd, WG160160_ADDRSL_REG, offset & 0xff);
+ write_reg(pdd, WG160160_ADDRSL_REG, (offset >> 8) & 0xff);
+
+ /* prepare to write data */
+ for (i = 0; i < PIN_NUM; i++)
+ ins[PIN_DB0 + i] = !!(WG160160_WRITE_REG & BIT(i));
+
+ gpiod_set_value_cansleep(pdd->bus->pin_rs, 1);
+ gpiod_set_array_value_cansleep(PIN_NUM, pdd->bus->data_pins->desc, ins);
+ wait_busy(pdd);
+ pardata_strobe_write(pdd);
+
+ /* Write data byte - by byte */
+ gpiod_set_value_cansleep(pdd->bus->pin_rs, 0);
+
+ for (i = offset; i < (offset + len); i++) {
+ for (bit = 0; bit < PIN_NUM; bit++)
+ val[PIN_DB0 + bit] = !!(data[i] & BIT(bit));
+
+ gpiod_set_array_value_cansleep(PIN_NUM,
+ pdd->bus->data_pins->desc,
+ val);
+ wait_busy(pdd);
+ pardata_strobe_write(pdd);
+ }
+
+ return 0;
+}
+
+static void wg160160_pipe_enable(struct drm_simple_display_pipe *pipe,
+ struct drm_crtc_state *crtc_state,
+ struct drm_plane_state *plane_state)
+{
+ struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
+ struct pardata_data *pdd = pardata_from_tinydrm(tdev);
+ int ret;
+
+ ret = pardata_poweron_reset(pdd);
+ if (ret)
+ return;
+
+ /* Init quence for WG160160 display */
+
+ /* Graphics mode, Master */
+ pardata_write_reg(pdd, WG160160_MODE_REG, MODE_GRAPHIC_DISP_ON);
+ /* Set PITCH to 8 bits/bytes */
+ pardata_write_reg(pdd, WG160160_PITCH_REG, 0x7);
+ /* Duty cycle is the vertical resolution */
+ pardata_write_reg(pdd, WG160160_DUTY_REG, 160);
+
+ /* Start address in display RAM */
+ pardata_write_reg(pdd, WG160160_ADDRSL_REG, 0x0);
+ pardata_write_reg(pdd, WG160160_ADDRSU_REG, 0x0);
+
+ pardata_enable_flush(pdd, crtc_state, plane_state);
+}
+
+static const struct drm_simple_display_pipe_funcs wg160160_pipe_funcs = {
+ .enable = wg160160_pipe_enable,
+ .disable = pardata_pipe_disable,
+ .update = tinydrm_display_pipe_update,
+ .prepare_fb = drm_gem_fb_simple_display_pipe_prepare_fb,
+};
+
+static const struct drm_display_mode wg160160_mode = {
+ TINYDRM_MODE(160, 160, 62, 62),
+};
+
+DEFINE_DRM_GEM_CMA_FOPS(wg160160_fops);
+
+static struct drm_driver wg160160_drm_driver = {
+ .driver_features = DRIVER_GEM |
+ DRIVER_MODESET |
+ DRIVER_PRIME |
+ DRIVER_ATOMIC,
+ .fops = &wg160160_fops,
+ TINYDRM_GEM_DRIVER_OPS,
+ .lastclose = drm_fb_helper_lastclose,
+ .name = "wg160160",
+ .desc = "Winstar WG160160",
+ .date = "20180808",
+ .major = 1,
+ .minor = 0,
+};
+
+static const struct of_device_id wg160160_of_match[] = {
+ { .compatible = "winstar,wg160160" },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, wg160160_of_match);
+
+static struct pardata_driver wg160160_pardata_driver;
+
+static int wg160160_probe(struct pardata_device *pddev)
+{
+ struct device *dev = &pddev->dev;
+ struct pardata_data *pdd;
+ int ret;
+
+ pdd = devm_kzalloc(dev, sizeof(*pdd), GFP_KERNEL);
+ if (!pdd)
+ return -ENOMEM;
+
+ /* Find all pins */
+ pdd->pin_reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
+ if (IS_ERR(pdd->pin_reset)) {
+ DRM_DEV_ERROR(dev, "Failed to get gpio 'reset'\n");
+ return PTR_ERR(pdd->pin_reset);
+ }
+
+ pdd->pin_cs = devm_gpiod_get(dev, "cs", GPIOD_OUT_HIGH);
+ if (IS_ERR(pdd->pin_cs)) {
+ DRM_DEV_ERROR(dev, "Failed to get gpio 'rs'\n");
+ return PTR_ERR(pdd->pin_cs);
+ }
+
+ pdd->backlight = devm_of_find_backlight(dev);
+ if (IS_ERR(pdd->backlight))
+ return PTR_ERR(pdd->backlight);
+
+ pdd->strobe_write = pardata_strobe_8080_write;
+ pdd->write_reg = write_reg;
+ pdd->write_buf = write_buf;
+
+ ret = pardata_init(dev, pdd, &wg160160_pipe_funcs,
+ &wg160160_drm_driver, &wg160160_mode);
+ if (ret)
+ return ret;
+
+ pardata_dev_set_drvdata(pddev, pdd);
+
+ return devm_tinydrm_register(&pdd->tinydrm);
+}
+
+static void wg160160_shutdown(struct pardata_device *pddev)
+{
+ struct pardata_data *dpp = pardata_dev_get_drvdata(pddev);
+
+ tinydrm_shutdown(&dpp->tinydrm);
+}
+
+static struct pardata_driver wg160160_pardata_driver = {
+ .driver = {
+ .name = "wg160160",
+ .owner = THIS_MODULE,
+ .of_match_table = wg160160_of_match,
+ },
+ .probe = wg160160_probe,
+ .shutdown = wg160160_shutdown,
+};
+module_pardata_driver(wg160160_pardata_driver);
+
+MODULE_DESCRIPTION("Winstar WG160160 DRM driver");
+MODULE_AUTHOR("Sam Ravnborg <sam at ravnborg.org>");
+MODULE_LICENSE("GPL v2");
--
2.12.0
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