Add support to convert from XR24 to reversed monochrome for drivers that control monochromatic display panels, that only have 1 bit per pixel.

The function does a line-by-line conversion doing an intermediate step first from XR24 to 8-bit grayscale and then to reversed monochrome.

The drm_fb_gray8_to_mono_reversed_line() helper was based on code from drivers/gpu/drm/tiny/repaper.c driver.

Signed-off-by: Javier Martinez Canillas javierm@redhat.com Reviewed-by: Thomas Zimmermann tzimmermann@suse.de ---

Changes in v4: - Rename end_offset to end_len (Thomas Zimmermann) - Warn once if dst_pitch is not a multiple of 8 (Thomas Zimmermann) - Drop drm_fb_gray8_to_mono_reversed() that's not used (Thomas Zimmermann) - Allocate single buffer for both copy cma memory and gray8 (Thomas Zimmermann) - Add Thomas Zimmermann Reviewed-by tag to patch adding XR24 -> mono helper.

Changes in v3: - Also add a drm_fb_xrgb8888_to_mono_reversed() helper (Thomas Zimmermann) - Split lines copy to drm_fb_gray8_to_mono_reversed_line() (Thomas Zimmermann) - Handle case where the source buffer is not aligned to 8 (Thomas Zimmermann)

drivers/gpu/drm/drm_format_helper.c | 107 ++++++++++++++++++++++++++++ include/drm/drm_format_helper.h | 4 ++ 2 files changed, 111 insertions(+)

diff --git a/drivers/gpu/drm/drm_format_helper.c b/drivers/gpu/drm/drm_format_helper.c index b981712623d3..ec4e3724ee79 100644 --- a/drivers/gpu/drm/drm_format_helper.c +++ b/drivers/gpu/drm/drm_format_helper.c @@ -591,3 +591,110 @@ int drm_fb_blit_toio(void __iomem *dst, unsigned int dst_pitch, uint32_t dst_for return -EINVAL; } EXPORT_SYMBOL(drm_fb_blit_toio); + +static void drm_fb_gray8_to_mono_reversed_line(u8 *dst, const u8 *src, unsigned int pixels, + unsigned int start_offset, unsigned int end_len) +{ + unsigned int xb, i; + + for (xb = 0; xb < pixels; xb++) { + unsigned int start = 0, end = 8; + u8 byte = 0x00; + + if (xb == 0 && start_offset) + start = start_offset; + + if (xb == pixels - 1 && end_len) + end = end_len; + + for (i = start; i < end; i++) { + unsigned int x = xb * 8 + i; + + byte >>= 1; + if (src[x] >> 7) + byte |= BIT(7); + } + *dst++ = byte; + } +} + +/** + * drm_fb_xrgb8888_to_mono_reversed - Convert XRGB8888 to reversed monochrome + * @dst: reversed monochrome destination buffer + * @dst_pitch: Number of bytes between two consecutive scanlines within dst + * @src: XRGB8888 source buffer + * @fb: DRM framebuffer + * @clip: Clip rectangle area to copy + * + * DRM doesn't have native monochrome support. + * Such drivers can announce the commonly supported XR24 format to userspace + * and use this function to convert to the native format. + * + * This function uses drm_fb_xrgb8888_to_gray8() to convert to grayscale and + * then the result is converted from grayscale to reversed monohrome. + */ +void drm_fb_xrgb8888_to_mono_reversed(void *dst, unsigned int dst_pitch, const void *vaddr, + const struct drm_framebuffer *fb, const struct drm_rect *clip) +{ + unsigned int linepixels = drm_rect_width(clip); + unsigned int lines = clip->y2 - clip->y1; + unsigned int cpp = fb->format->cpp[0]; + unsigned int len_src32 = linepixels * cpp; + unsigned int start_offset, end_len; + unsigned int y; + u8 *mono = dst, *gray8; + u32 *src32; + + if (WARN_ON(fb->format->format != DRM_FORMAT_XRGB8888)) + return; + + /* + * The reversed mono destination buffer contains 1 bit per pixel + * and destination scanlines have to be in multiple of 8 pixels. + */ + if (!dst_pitch) + dst_pitch = DIV_ROUND_UP(linepixels, 8); + + WARN_ONCE(dst_pitch % 8 != 0, "dst_pitch is not a multiple of 8\n"); + + /* + * The cma memory is write-combined so reads are uncached. + * Speed up by fetching one line at a time. + * + * Also, format conversion from XR24 to reversed monochrome + * are done line-by-line but are converted to 8-bit grayscale + * as an intermediate step. + * + * Allocate a buffer to be used for both copying from the cma + * memory and to store the intermediate grayscale line pixels. + */ + src32 = kmalloc(len_src32 + linepixels, GFP_KERNEL); + if (!src32) + return; + + gray8 = (u8 *)src32 + len_src32; + + /* + * For damage handling, it is possible that only parts of the source + * buffer is copied and this could lead to start and end pixels that + * are not aligned to multiple of 8. + * + * Calculate if the start and end pixels are not aligned and set the + * offsets for the reversed mono line conversion function to adjust. + */ + start_offset = clip->x1 % 8; + end_len = clip->x2 % 8; + + vaddr += clip_offset(clip, fb->pitches[0], cpp); + for (y = 0; y < lines; y++) { + src32 = memcpy(src32, vaddr, len_src32); + drm_fb_xrgb8888_to_gray8_line(gray8, src32, linepixels); + drm_fb_gray8_to_mono_reversed_line(mono, gray8, dst_pitch, + start_offset, end_len); + vaddr += fb->pitches[0]; + mono += dst_pitch; + } + + kfree(src32); +} +EXPORT_SYMBOL(drm_fb_xrgb8888_to_mono_reversed); diff --git a/include/drm/drm_format_helper.h b/include/drm/drm_format_helper.h index b30ed5de0a33..0b0937c0b2f6 100644 --- a/include/drm/drm_format_helper.h +++ b/include/drm/drm_format_helper.h @@ -43,4 +43,8 @@ int drm_fb_blit_toio(void __iomem *dst, unsigned int dst_pitch, uint32_t dst_for const void *vmap, const struct drm_framebuffer *fb, const struct drm_rect *rect);

+void drm_fb_xrgb8888_to_mono_reversed(void *dst, unsigned int dst_pitch, const void *src, + const struct drm_framebuffer *fb, + const struct drm_rect *clip); + #endif /* __LINUX_DRM_FORMAT_HELPER_H */

This adds a DRM driver for SSD1305, SSD1306, SSD1307 and SSD1309 Solomon OLED display controllers.

It's only the core part of the driver and a bus specific driver is needed for each transport interface supported by the display controllers.

Signed-off-by: Javier Martinez Canillas javierm@redhat.com ---

Changes in v4: - Rename vbat supply to vcc since is how's labeled in the device (Mark Brown) - Don't make the regulator option since is always needed (Mark Brown) - Add solomon Kconfig source and directory inclusion sorted (Andy Shevchenko) - Use SSD130x instead of SSD130X to denote is not a model name (Andy Shevchenko) - Check if there's a reset pin in the callee and not the caller (Andy Shevchenko) - Define missing commands instead of using magic numbers (Andy Shevchenko) - Use GENMASK() and FIELD_PREP() macros when possible (Andy Shevchenko) - Avoid using ternary operators to ease code readablity (Andy Shevchenko) - Use i++ instead of --i on some for loops (Andy Shevchenko) - Remove redundant blank lines (Andy Shevchenko) - Rename power_off label to out_power_off (Andy Shevchenko) - Use dev_err_probe() even if no -EPROBE_DEFER (Andy Shevchenko) - Don't use plural Authors if there's only one (Andy Shevchenko)

Changes in v3: - Move driver from tiny sub-dir to drivers/gpu/drm/solomon (Sam Ravnborg) - Split driver in a bus agnostic core and bus specific (Andy Shevchenko) - Use regmap to access the chip registers (Andy Shevchenko) - Remove unnecessary blank lines (Andy Shevchenko) - Remove unneeded inline specifier in functions (Andy Shevchenko) - Add a comment about always returning a single mode (Andy Shevchenko) - Change write command logic to use do while loop (Andy Shevchenko) - Use "firmware description" instead of "device tree" (Andy Shevchenko) - Use return foo() instead of returning the return value (Andy Shevchenko) - Don't split lines longer than 80 chars if makes less readable (Andy Shevchenko) - Remove redundant else statements in .mode_valid callback (Andy Shevchenko) - Rename powero{n,ff}() functions to power_o{n,ff)() (Andy Shevchenko) - Use dev_err_probe() to prevent spam logs on probe deferral (Andy Shevchenko) - Remove ',' after sentinel terminator in array (Andy Shevchenko) - Fix a bug when doing partial updates (Geert Uytterhoeven)

Changes in v2: - Drop patch that was adding a DRM_MODE_CONNECTOR_I2C type. - Invert order of backlight {en,dis}able and display {on,off} (Sam Ravnborg) - Don't clear the screen and turn on display on probe (Sam Ravnborg) - Use backlight_get_brightness() macro to get BL brightness (Sam Ravnborg) - Use dev managed version of devm_backlight_device_register() (Sam Ravnborg) - Use dev_name(dev) for backlight name instead of an array (Sam Ravnborg) - Drop the .get_brightness callback since isn't needed (Sam Ravnborg) - Rename driver to ssd130x since supports a display family (Thomas Zimmermann) - Drop the TINY prefix from the Kconfig symbol (Thomas Zimmermann) - Sort the Kconfig symbol dependencies alphabetically (Thomas Zimmermann) - Rename struct ssd130x_array to struct ssd130x_i2c_msg (Thomas Zimmermann) - Rename struct ssd130x_i2c_msg .type member to .cmd (Thomas Zimmermann) - Use sizeof(*foo) instead of sizeof(struct foo) (Thomas Zimmermann) - Use struct_size() macro to calculate sizeof(*foo) + len (Thomas Zimmermann) - Use kcalloc() instead of kmalloc_array() + memset() (Thomas Zimmermann) - Use shadow plane helpers virtual screen support (Thomas Zimmermann) - Remove unused goto label in ssd1307_fb_blit_rect() (Thomas Zimmermann) - Use drm_set_preferred_mode() inset of manually set (Thomas Zimmermann) - Use shadow plane helpers virtual screen support (Thomas Zimmermann) - Remove unused goto label in ssd1307_fb_blit_rect() (Thomas Zimmermann) - Use drm_set_preferred_mode() inset of manually set (Thomas Zimmermann) - Reorganize code in probe to make it more legible (Thomas Zimmermann) - ssd130x_write_cmd() uses varargs to simplify I2C code (Thomas Zimmermann) - Move regulator/pwm init logic to display pipe enable callback.

drivers/gpu/drm/Kconfig | 2 + drivers/gpu/drm/Makefile | 1 + drivers/gpu/drm/solomon/Kconfig | 12 + drivers/gpu/drm/solomon/Makefile | 1 + drivers/gpu/drm/solomon/ssd130x.c | 852 ++++++++++++++++++++++++++++++ drivers/gpu/drm/solomon/ssd130x.h | 76 +++ 6 files changed, 944 insertions(+) create mode 100644 drivers/gpu/drm/solomon/Kconfig create mode 100644 drivers/gpu/drm/solomon/Makefile create mode 100644 drivers/gpu/drm/solomon/ssd130x.c create mode 100644 drivers/gpu/drm/solomon/ssd130x.h

diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig index dfdd3ec5f793..763355330b17 100644 --- a/drivers/gpu/drm/Kconfig +++ b/drivers/gpu/drm/Kconfig @@ -403,6 +403,8 @@ source "drivers/gpu/drm/xlnx/Kconfig"

source "drivers/gpu/drm/gud/Kconfig"

+source "drivers/gpu/drm/solomon/Kconfig" + source "drivers/gpu/drm/sprd/Kconfig"

config DRM_HYPERV diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile index 8675c2af7ae1..c2ef5f9fce54 100644 --- a/drivers/gpu/drm/Makefile +++ b/drivers/gpu/drm/Makefile @@ -132,4 +132,5 @@ obj-$(CONFIG_DRM_TIDSS) += tidss/ obj-y += xlnx/ obj-y += gud/ obj-$(CONFIG_DRM_HYPERV) += hyperv/ +obj-y += solomon/ obj-$(CONFIG_DRM_SPRD) += sprd/ diff --git a/drivers/gpu/drm/solomon/Kconfig b/drivers/gpu/drm/solomon/Kconfig new file mode 100644 index 000000000000..7720a7039e8d --- /dev/null +++ b/drivers/gpu/drm/solomon/Kconfig @@ -0,0 +1,12 @@ +config DRM_SSD130X + tristate "DRM support for Solomon SSD130x OLED displays" + depends on DRM + select BACKLIGHT_CLASS_DEVICE + select DRM_GEM_SHMEM_HELPER + select DRM_KMS_HELPER + help + DRM driver for the SSD1305, SSD1306, SSD1307 and SSD1309 Solomon + OLED controllers. This is only for the core driver, a driver for + the appropriate bus transport in your chip also must be selected. + + If M is selected the module will be called ssd130x. diff --git a/drivers/gpu/drm/solomon/Makefile b/drivers/gpu/drm/solomon/Makefile new file mode 100644 index 000000000000..f685addb19fe --- /dev/null +++ b/drivers/gpu/drm/solomon/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_DRM_SSD130X) += ssd130x.o diff --git a/drivers/gpu/drm/solomon/ssd130x.c b/drivers/gpu/drm/solomon/ssd130x.c new file mode 100644 index 000000000000..e17cf52b222e --- /dev/null +++ b/drivers/gpu/drm/solomon/ssd130x.c @@ -0,0 +1,852 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * DRM driver for Solomon SSD130x OLED displays + * + * Copyright 2022 Red Hat Inc. + * Author: Javier Martinez Canillas javierm@redhat.com + * + * Based on drivers/video/fbdev/ssd1307fb.c + * Copyright 2012 Free Electrons + */ + +#include <linux/backlight.h> +#include <linux/bitfield.h> +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/property.h> +#include <linux/pwm.h> +#include <linux/regulator/consumer.h> + +#include <drm/drm_atomic_helper.h> +#include <drm/drm_damage_helper.h> +#include <drm/drm_fb_cma_helper.h> +#include <drm/drm_fb_helper.h> +#include <drm/drm_format_helper.h> +#include <drm/drm_gem_atomic_helper.h> +#include <drm/drm_gem_framebuffer_helper.h> +#include <drm/drm_gem_shmem_helper.h> +#include <drm/drm_managed.h> +#include <drm/drm_modes.h> +#include <drm/drm_rect.h> +#include <drm/drm_probe_helper.h> + +#include "ssd130x.h" + +#define DRIVER_NAME "ssd130x" +#define DRIVER_DESC "DRM driver for Solomon SSD130x OLED displays" +#define DRIVER_DATE "20220131" +#define DRIVER_MAJOR 1 +#define DRIVER_MINOR 0 + +#define SSD130X_DATA 0x40 +#define SSD130X_COMMAND 0x80 + +#define SSD130X_SET_ADDRESS_MODE 0x20 +#define SSD130X_SET_COL_RANGE 0x21 +#define SSD130X_SET_PAGE_RANGE 0x22 +#define SSD130X_CONTRAST 0x81 +#define SSD130X_SET_LOOKUP_TABLE 0x91 +#define SSD130X_CHARGE_PUMP 0x8d +#define SSD130X_SEG_REMAP_ON 0xa1 +#define SSD130X_DISPLAY_OFF 0xae +#define SSD130X_SET_MULTIPLEX_RATIO 0xa8 +#define SSD130X_DISPLAY_ON 0xaf +#define SSD130X_START_PAGE_ADDRESS 0xb0 +#define SSD130X_SET_COM_SCAN_DIR 0xc0 +#define SSD130X_SET_DISPLAY_OFFSET 0xd3 +#define SSD130X_SET_CLOCK_FREQ 0xd5 +#define SSD130X_SET_AREA_COLOR_MODE 0xd8 +#define SSD130X_SET_PRECHARGE_PERIOD 0xd9 +#define SSD130X_SET_COM_PINS_CONFIG 0xda +#define SSD130X_SET_VCOMH 0xdb + +#define SSD130X_SET_COM_SCAN_DIR_MASK GENMASK(3, 2) +#define SSD130X_SET_COM_SCAN_DIR_SET(val) FIELD_PREP(SSD130X_SET_COM_SCAN_DIR_MASK, (val)) +#define SSD130X_SET_CLOCK_DIV_MASK GENMASK(3, 0) +#define SSD130X_SET_CLOCK_DIV_SET(val) FIELD_PREP(SSD130X_SET_CLOCK_DIV_MASK, (val)) +#define SSD130X_SET_CLOCK_FREQ_MASK GENMASK(7, 4) +#define SSD130X_SET_CLOCK_FREQ_SET(val) FIELD_PREP(SSD130X_SET_CLOCK_FREQ_MASK, (val)) +#define SSD130X_SET_PRECHARGE_PERIOD1_MASK GENMASK(3, 0) +#define SSD130X_SET_PRECHARGE_PERIOD1_SET(val) FIELD_PREP(SSD130X_SET_PRECHARGE_PERIOD1_MASK, (val)) +#define SSD130X_SET_PRECHARGE_PERIOD2_MASK GENMASK(7, 4) +#define SSD130X_SET_PRECHARGE_PERIOD2_SET(val) FIELD_PREP(SSD130X_SET_PRECHARGE_PERIOD2_MASK, (val)) +#define SSD130X_SET_COM_PINS_CONFIG1_MASK GENMASK(4, 4) +#define SSD130X_SET_COM_PINS_CONFIG1_SET(val) FIELD_PREP(SSD130X_SET_COM_PINS_CONFIG1_MASK, (!val)) +#define SSD130X_SET_COM_PINS_CONFIG2_MASK GENMASK(5, 5) +#define SSD130X_SET_COM_PINS_CONFIG2_SET(val) FIELD_PREP(SSD130X_SET_COM_PINS_CONFIG2_MASK, (val)) + +#define SSD130X_SET_ADDRESS_MODE_HORIZONTAL (0x00) +#define SSD130X_SET_ADDRESS_MODE_VERTICAL (0x01) +#define SSD130X_SET_ADDRESS_MODE_PAGE (0x02) + +#define SSD130X_SET_AREA_COLOR_MODE_ENABLE (0x1e) +#define SSD130X_SET_AREA_COLOR_MODE_LOW_POWER (0x05) + +#define MAX_CONTRAST 255 + +static inline struct ssd130x_device *drm_to_ssd130x(struct drm_device *drm) +{ + return container_of(drm, struct ssd130x_device, drm); +} + +/* + * Helper to write data (SSD130X_DATA) to the device. + */ +static int ssd130x_write_data(struct ssd130x_device *ssd130x, u8 *values, int count) +{ + int ret; + + ret = regmap_bulk_write(ssd130x->regmap, SSD130X_DATA, values, count); + if (ret) + return ret; + + return 0; +} + +/* + * Helper to write command (SSD130X_COMMAND). The fist variadic argument + * is the command to write and the following are the command options. + */ +static int ssd130x_write_cmd(struct ssd130x_device *ssd130x, int count, + /* u8 cmd, u8 option, ... */...) +{ + va_list ap; + u8 value; + int ret; + + va_start(ap, count); + + do { + value = va_arg(ap, int); + ret = regmap_write(ssd130x->regmap, SSD130X_COMMAND, (u8)value); + if (ret) + goto out_end; + } while (--count); + +out_end: + va_end(ap); + + return ret; +} + +static int ssd130x_set_col_range(struct ssd130x_device *ssd130x, + u8 col_start, u8 cols) +{ + u8 col_end = col_start + cols - 1; + int ret; + + if (col_start == ssd130x->col_start && col_end == ssd130x->col_end) + return 0; + + ret = ssd130x_write_cmd(ssd130x, 3, SSD130X_SET_COL_RANGE, col_start, col_end); + if (ret < 0) + return ret; + + ssd130x->col_start = col_start; + ssd130x->col_end = col_end; + return 0; +} + +static int ssd130x_set_page_range(struct ssd130x_device *ssd130x, + u8 page_start, u8 pages) +{ + u8 page_end = page_start + pages - 1; + int ret; + + if (page_start == ssd130x->page_start && page_end == ssd130x->page_end) + return 0; + + ret = ssd130x_write_cmd(ssd130x, 3, SSD130X_SET_PAGE_RANGE, page_start, page_end); + if (ret < 0) + return ret; + + ssd130x->page_start = page_start; + ssd130x->page_end = page_end; + return 0; +} + +static int ssd130x_pwm_enable(struct ssd130x_device *ssd130x) +{ + struct device *dev = ssd130x->dev; + struct pwm_state pwmstate; + + ssd130x->pwm = pwm_get(dev, NULL); + if (IS_ERR(ssd130x->pwm)) { + dev_err(dev, "Could not get PWM from firmware description!\n"); + return PTR_ERR(ssd130x->pwm); + } + + pwm_init_state(ssd130x->pwm, &pwmstate); + pwm_set_relative_duty_cycle(&pwmstate, 50, 100); + pwm_apply_state(ssd130x->pwm, &pwmstate); + + /* Enable the PWM */ + pwm_enable(ssd130x->pwm); + + dev_dbg(dev, "Using PWM%d with a %lluns period.\n", + ssd130x->pwm->pwm, pwm_get_period(ssd130x->pwm)); + + return 0; +} + +static void ssd130x_reset(struct ssd130x_device *ssd130x) +{ + if (!ssd130x->reset) + return; + + /* Reset the screen */ + gpiod_set_value_cansleep(ssd130x->reset, 1); + udelay(4); + gpiod_set_value_cansleep(ssd130x->reset, 0); + udelay(4); +} + +static int ssd130x_power_on(struct ssd130x_device *ssd130x) +{ + struct device *dev = ssd130x->dev; + int ret; + + ssd130x_reset(ssd130x); + + ret = regulator_enable(ssd130x->vcc_reg); + if (ret) { + dev_err(dev, "Failed to enable VCC: %d\n", ret); + return ret; + } + + if (ssd130x->device_info->need_pwm) { + ret = ssd130x_pwm_enable(ssd130x); + if (ret) { + dev_err(dev, "Failed to enable PWM: %d\n", ret); + regulator_disable(ssd130x->vcc_reg); + return ret; + } + } + + return 0; +} + +static void ssd130x_power_off(struct ssd130x_device *ssd130x) +{ + if (ssd130x->device_info->need_pwm) { + pwm_disable(ssd130x->pwm); + pwm_put(ssd130x->pwm); + } + + regulator_disable(ssd130x->vcc_reg); +} + +static int ssd130x_init(struct ssd130x_device *ssd130x) +{ + u32 precharge, dclk, com_invdir, compins, chargepump; + int ret; + + /* Set initial contrast */ + ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_CONTRAST, ssd130x->contrast); + if (ret < 0) + return ret; + + /* Set segment re-map */ + if (ssd130x->seg_remap) { + ret = ssd130x_write_cmd(ssd130x, 1, SSD130X_SEG_REMAP_ON); + if (ret < 0) + return ret; + } + + /* Set COM direction */ + com_invdir = (SSD130X_SET_COM_SCAN_DIR | + SSD130X_SET_COM_SCAN_DIR_SET(ssd130x->com_invdir)); + ret = ssd130x_write_cmd(ssd130x, 1, com_invdir); + if (ret < 0) + return ret; + + /* Set multiplex ratio value */ + ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_MULTIPLEX_RATIO, ssd130x->height - 1); + if (ret < 0) + return ret; + + /* set display offset value */ + ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_DISPLAY_OFFSET, ssd130x->com_offset); + if (ret < 0) + return ret; + + /* Set clock frequency */ + dclk = (SSD130X_SET_CLOCK_DIV_SET(ssd130x->dclk_div - 1) | + SSD130X_SET_CLOCK_FREQ_SET(ssd130x->dclk_frq)); + ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_CLOCK_FREQ, dclk); + if (ret < 0) + return ret; + + /* Set Area Color Mode ON/OFF & Low Power Display Mode */ + if (ssd130x->area_color_enable || ssd130x->low_power) { + u32 mode = 0; + + if (ssd130x->area_color_enable) + mode |= SSD130X_SET_AREA_COLOR_MODE_ENABLE; + + if (ssd130x->low_power) + mode |= SSD130X_SET_AREA_COLOR_MODE_LOW_POWER; + + ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_AREA_COLOR_MODE, mode); + if (ret < 0) + return ret; + } + + /* Set precharge period in number of ticks from the internal clock */ + precharge = (SSD130X_SET_PRECHARGE_PERIOD1_SET(ssd130x->prechargep1) | + SSD130X_SET_PRECHARGE_PERIOD1_SET(ssd130x->prechargep2)); + ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_PRECHARGE_PERIOD, precharge); + if (ret < 0) + return ret; + + /* Set COM pins configuration */ + compins = BIT(1); + compins |= (SSD130X_SET_COM_PINS_CONFIG1_SET(ssd130x->com_seq) | + SSD130X_SET_COM_PINS_CONFIG2_SET(ssd130x->com_lrremap)); + ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_COM_PINS_CONFIG, compins); + if (ret < 0) + return ret; + + + /* Set VCOMH */ + ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_VCOMH, ssd130x->vcomh); + if (ret < 0) + return ret; + + /* Turn on the DC-DC Charge Pump */ + chargepump = BIT(4); + + if (ssd130x->device_info->need_chargepump) + chargepump |= BIT(2); + + ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_CHARGE_PUMP, chargepump); + if (ret < 0) + return ret; + + /* Set lookup table */ + if (ssd130x->lookup_table_set) { + int i; + + ret = ssd130x_write_cmd(ssd130x, 1, SSD130X_SET_LOOKUP_TABLE); + if (ret < 0) + return ret; + + for (i = 0; i < ARRAY_SIZE(ssd130x->lookup_table); i++) { + u8 val = ssd130x->lookup_table[i]; + + if (val < 31 || val > 63) + dev_warn(ssd130x->dev, + "lookup table index %d value out of range 31 <= %d <= 63\n", + i, val); + ret = ssd130x_write_cmd(ssd130x, 1, val); + if (ret < 0) + return ret; + } + } + + /* Switch to horizontal addressing mode */ + return ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_ADDRESS_MODE, + SSD130X_SET_ADDRESS_MODE_HORIZONTAL); +} + +static int ssd130x_update_rect(struct ssd130x_device *ssd130x, u8 *buf, + struct drm_rect *rect) +{ + unsigned int x = rect->x1; + unsigned int y = rect->y1; + unsigned int width = drm_rect_width(rect); + unsigned int height = drm_rect_height(rect); + unsigned int line_length = DIV_ROUND_UP(width, 8); + unsigned int pages = DIV_ROUND_UP(y % 8 + height, 8); + u32 array_idx = 0; + int ret, i, j, k; + u8 *data_array = NULL; + + data_array = kcalloc(width, pages, GFP_KERNEL); + if (!data_array) + return -ENOMEM; + + /* + * The screen is divided in pages, each having a height of 8 + * pixels, and the width of the screen. When sending a byte of + * data to the controller, it gives the 8 bits for the current + * column. I.e, the first byte are the 8 bits of the first + * column, then the 8 bits for the second column, etc. + * + * + * Representation of the screen, assuming it is 5 bits + * wide. Each letter-number combination is a bit that controls + * one pixel. + * + * A0 A1 A2 A3 A4 + * B0 B1 B2 B3 B4 + * C0 C1 C2 C3 C4 + * D0 D1 D2 D3 D4 + * E0 E1 E2 E3 E4 + * F0 F1 F2 F3 F4 + * G0 G1 G2 G3 G4 + * H0 H1 H2 H3 H4 + * + * If you want to update this screen, you need to send 5 bytes: + * (1) A0 B0 C0 D0 E0 F0 G0 H0 + * (2) A1 B1 C1 D1 E1 F1 G1 H1 + * (3) A2 B2 C2 D2 E2 F2 G2 H2 + * (4) A3 B3 C3 D3 E3 F3 G3 H3 + * (5) A4 B4 C4 D4 E4 F4 G4 H4 + */ + + ret = ssd130x_set_col_range(ssd130x, ssd130x->col_offset + x, width); + if (ret < 0) + goto out_free; + + ret = ssd130x_set_page_range(ssd130x, ssd130x->page_offset + y / 8, pages); + if (ret < 0) + goto out_free; + + for (i = y / 8; i < y / 8 + pages; i++) { + int m = 8; + + /* Last page may be partial */ + if (8 * (i + 1) > ssd130x->height) + m = ssd130x->height % 8; + for (j = x; j < x + width; j++) { + u8 data = 0; + + for (k = 0; k < m; k++) { + u8 byte = buf[(8 * i + k) * line_length + j / 8]; + u8 bit = (byte >> (j % 8)) & 1; + + data |= bit << k; + } + data_array[array_idx++] = data; + } + } + + ret = ssd130x_write_data(ssd130x, data_array, width * pages); + +out_free: + kfree(data_array); + return ret; +} + +static void ssd130x_clear_screen(struct ssd130x_device *ssd130x) +{ + u8 *buf = NULL; + struct drm_rect fullscreen = { + .x1 = 0, + .x2 = ssd130x->width, + .y1 = 0, + .y2 = ssd130x->height, + }; + + buf = kcalloc(ssd130x->width, ssd130x->height, GFP_KERNEL); + if (!buf) + return; + + ssd130x_update_rect(ssd130x, buf, &fullscreen); + + kfree(buf); +} + +static int ssd130x_fb_blit_rect(struct drm_framebuffer *fb, const struct dma_buf_map *map, + struct drm_rect *rect) +{ + struct ssd130x_device *ssd130x = drm_to_ssd130x(fb->dev); + void *vmap = map->vaddr; /* TODO: Use mapping abstraction properly */ + int ret = 0; + u8 *buf = NULL; + + buf = kcalloc(fb->width, fb->height, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + drm_fb_xrgb8888_to_mono_reversed(buf, 0, vmap, fb, rect); + + ssd130x_update_rect(ssd130x, buf, rect); + + kfree(buf); + + return ret; +} + +static int ssd130x_display_pipe_mode_valid(struct drm_simple_display_pipe *pipe, + const struct drm_display_mode *mode) +{ + struct ssd130x_device *ssd130x = drm_to_ssd130x(pipe->crtc.dev); + + if (mode->hdisplay != ssd130x->mode.hdisplay && + mode->vdisplay != ssd130x->mode.vdisplay) + return MODE_ONE_SIZE; + + if (mode->hdisplay != ssd130x->mode.hdisplay) + return MODE_ONE_WIDTH; + + if (mode->vdisplay != ssd130x->mode.vdisplay) + return MODE_ONE_HEIGHT; + + return MODE_OK; +} + +static void ssd130x_display_pipe_enable(struct drm_simple_display_pipe *pipe, + struct drm_crtc_state *crtc_state, + struct drm_plane_state *plane_state) +{ + struct ssd130x_device *ssd130x = drm_to_ssd130x(pipe->crtc.dev); + struct drm_device *drm = &ssd130x->drm; + int idx, ret; + + ret = ssd130x_power_on(ssd130x); + if (ret) + return; + + ret = ssd130x_init(ssd130x); + if (ret) + goto out_power_off; + + if (!drm_dev_enter(drm, &idx)) + goto out_power_off; + + ssd130x_clear_screen(ssd130x); + + ssd130x_write_cmd(ssd130x, 1, SSD130X_DISPLAY_ON); + + backlight_enable(ssd130x->bl_dev); + + drm_dev_exit(idx); + + return; +out_power_off: + ssd130x_power_off(ssd130x); +} + +static void ssd130x_display_pipe_disable(struct drm_simple_display_pipe *pipe) +{ + struct ssd130x_device *ssd130x = drm_to_ssd130x(pipe->crtc.dev); + struct drm_device *drm = &ssd130x->drm; + int idx; + + if (!drm_dev_enter(drm, &idx)) + return; + + ssd130x_clear_screen(ssd130x); + + backlight_disable(ssd130x->bl_dev); + + ssd130x_write_cmd(ssd130x, 1, SSD130X_DISPLAY_OFF); + + ssd130x_power_off(ssd130x); + + drm_dev_exit(idx); +} + +static void ssd130x_display_pipe_update(struct drm_simple_display_pipe *pipe, + struct drm_plane_state *old_plane_state) +{ + struct ssd130x_device *ssd130x = drm_to_ssd130x(pipe->crtc.dev); + struct drm_plane_state *plane_state = pipe->plane.state; + struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state); + struct drm_framebuffer *fb = plane_state->fb; + struct drm_device *drm = &ssd130x->drm; + struct drm_rect src_clip, dst_clip; + int idx; + + if (!fb) + return; + + if (!pipe->crtc.state->active) + return; + + if (!drm_atomic_helper_damage_merged(old_plane_state, plane_state, &src_clip)) + return; + + dst_clip = plane_state->dst; + if (!drm_rect_intersect(&dst_clip, &src_clip)) + return; + + if (!drm_dev_enter(drm, &idx)) + return; + + ssd130x_fb_blit_rect(plane_state->fb, &shadow_plane_state->data[0], &dst_clip); + + drm_dev_exit(idx); +} + +static const struct drm_simple_display_pipe_funcs ssd130x_pipe_funcs = { + .mode_valid = ssd130x_display_pipe_mode_valid, + .enable = ssd130x_display_pipe_enable, + .disable = ssd130x_display_pipe_disable, + .update = ssd130x_display_pipe_update, + DRM_GEM_SIMPLE_DISPLAY_PIPE_SHADOW_PLANE_FUNCS, +}; + +static int ssd130x_connector_get_modes(struct drm_connector *connector) +{ + struct ssd130x_device *ssd130x = drm_to_ssd130x(connector->dev); + struct drm_display_mode *mode = &ssd130x->mode; + struct device *dev = ssd130x->dev; + + mode = drm_mode_duplicate(connector->dev, &ssd130x->mode); + if (!mode) { + dev_err(dev, "Failed to duplicated mode\n"); + return 0; + } + + drm_mode_probed_add(connector, mode); + drm_set_preferred_mode(connector, mode->hdisplay, mode->vdisplay); + + /* There is only a single mode */ + return 1; +} + +static const struct drm_connector_helper_funcs ssd130x_connector_helper_funcs = { + .get_modes = ssd130x_connector_get_modes, +}; + +static const struct drm_connector_funcs ssd130x_connector_funcs = { + .reset = drm_atomic_helper_connector_reset, + .fill_modes = drm_helper_probe_single_connector_modes, + .destroy = drm_connector_cleanup, + .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, + .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, +}; + +static const struct drm_mode_config_funcs ssd130x_mode_config_funcs = { + .fb_create = drm_gem_fb_create_with_dirty, + .atomic_check = drm_atomic_helper_check, + .atomic_commit = drm_atomic_helper_commit, +}; + +static const uint32_t ssd130x_formats[] = { + DRM_FORMAT_XRGB8888, +}; + +DEFINE_DRM_GEM_FOPS(ssd130x_fops); + +static const struct drm_driver ssd130x_drm_driver = { + DRM_GEM_SHMEM_DRIVER_OPS, + .name = DRIVER_NAME, + .desc = DRIVER_DESC, + .date = DRIVER_DATE, + .major = DRIVER_MAJOR, + .minor = DRIVER_MINOR, + .driver_features = DRIVER_ATOMIC | DRIVER_GEM | DRIVER_MODESET, + .fops = &ssd130x_fops, +}; + +static int ssd130x_update_bl(struct backlight_device *bdev) +{ + struct ssd130x_device *ssd130x = bl_get_data(bdev); + int brightness = backlight_get_brightness(bdev); + int ret; + + ssd130x->contrast = brightness; + + ret = ssd130x_write_cmd(ssd130x, 1, SSD130X_CONTRAST); + if (ret < 0) + return ret; + + ret = ssd130x_write_cmd(ssd130x, 1, ssd130x->contrast); + if (ret < 0) + return ret; + + return 0; +} + +static const struct backlight_ops ssd130xfb_bl_ops = { + .update_status = ssd130x_update_bl, +}; + +static void ssd130x_parse_properties(struct ssd130x_device *ssd130x) +{ + struct device *dev = ssd130x->dev; + + if (device_property_read_u32(dev, "solomon,width", &ssd130x->width)) + ssd130x->width = 96; + + if (device_property_read_u32(dev, "solomon,height", &ssd130x->height)) + ssd130x->height = 16; + + if (device_property_read_u32(dev, "solomon,page-offset", &ssd130x->page_offset)) + ssd130x->page_offset = 1; + + if (device_property_read_u32(dev, "solomon,col-offset", &ssd130x->col_offset)) + ssd130x->col_offset = 0; + + if (device_property_read_u32(dev, "solomon,com-offset", &ssd130x->com_offset)) + ssd130x->com_offset = 0; + + if (device_property_read_u32(dev, "solomon,prechargep1", &ssd130x->prechargep1)) + ssd130x->prechargep1 = 2; + + if (device_property_read_u32(dev, "solomon,prechargep2", &ssd130x->prechargep2)) + ssd130x->prechargep2 = 2; + + if (!device_property_read_u8_array(dev, "solomon,lookup-table", + ssd130x->lookup_table, + ARRAY_SIZE(ssd130x->lookup_table))) + ssd130x->lookup_table_set = 1; + + ssd130x->seg_remap = !device_property_read_bool(dev, "solomon,segment-no-remap"); + ssd130x->com_seq = device_property_read_bool(dev, "solomon,com-seq"); + ssd130x->com_lrremap = device_property_read_bool(dev, "solomon,com-lrremap"); + ssd130x->com_invdir = device_property_read_bool(dev, "solomon,com-invdir"); + ssd130x->area_color_enable = + device_property_read_bool(dev, "solomon,area-color-enable"); + ssd130x->low_power = device_property_read_bool(dev, "solomon,low-power"); + + ssd130x->contrast = 127; + ssd130x->vcomh = ssd130x->device_info->default_vcomh; + + /* Setup display timing */ + if (device_property_read_u32(dev, "solomon,dclk-div", &ssd130x->dclk_div)) + ssd130x->dclk_div = ssd130x->device_info->default_dclk_div; + if (device_property_read_u32(dev, "solomon,dclk-frq", &ssd130x->dclk_frq)) + ssd130x->dclk_frq = ssd130x->device_info->default_dclk_frq; +} + +static int ssd130x_init_modeset(struct ssd130x_device *ssd130x) +{ + struct drm_display_mode *mode = &ssd130x->mode; + struct device *dev = ssd130x->dev; + struct drm_device *drm = &ssd130x->drm; + unsigned long max_width, max_height; + int ret; + + ret = drmm_mode_config_init(drm); + if (ret) { + dev_err(dev, "DRM mode config init failed: %d\n", ret); + return ret; + } + + mode->type = DRM_MODE_TYPE_DRIVER; + mode->clock = 1; + mode->hdisplay = mode->htotal = ssd130x->width; + mode->hsync_start = mode->hsync_end = ssd130x->width; + mode->vdisplay = mode->vtotal = ssd130x->height; + mode->vsync_start = mode->vsync_end = ssd130x->height; + mode->width_mm = 27; + mode->height_mm = 27; + + max_width = max_t(unsigned long, mode->hdisplay, DRM_SHADOW_PLANE_MAX_WIDTH); + max_height = max_t(unsigned long, mode->vdisplay, DRM_SHADOW_PLANE_MAX_HEIGHT); + + drm->mode_config.min_width = mode->hdisplay; + drm->mode_config.max_width = max_width; + drm->mode_config.min_height = mode->vdisplay; + drm->mode_config.max_height = max_height; + drm->mode_config.preferred_depth = 32; + drm->mode_config.funcs = &ssd130x_mode_config_funcs; + + ret = drm_connector_init(drm, &ssd130x->connector, &ssd130x_connector_funcs, + DRM_MODE_CONNECTOR_Unknown); + if (ret) { + dev_err(dev, "DRM connector init failed: %d\n", ret); + return ret; + } + + drm_connector_helper_add(&ssd130x->connector, &ssd130x_connector_helper_funcs); + + ret = drm_simple_display_pipe_init(drm, &ssd130x->pipe, &ssd130x_pipe_funcs, + ssd130x_formats, ARRAY_SIZE(ssd130x_formats), + NULL, &ssd130x->connector); + if (ret) { + dev_err(dev, "DRM simple display pipeline init failed: %d\n", ret); + return ret; + } + + drm_plane_enable_fb_damage_clips(&ssd130x->pipe.plane); + + drm_mode_config_reset(drm); + + return 0; +} + +static int ssd130x_get_resources(struct ssd130x_device *ssd130x) +{ + struct device *dev = ssd130x->dev; + + ssd130x->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW); + if (IS_ERR(ssd130x->reset)) + return dev_err_probe(dev, PTR_ERR(ssd130x->reset), + "Failed to get reset gpio\n"); + + ssd130x->vcc_reg = devm_regulator_get(dev, "vcc"); + if (IS_ERR(ssd130x->vcc_reg)) + return dev_err_probe(dev, PTR_ERR(ssd130x->vcc_reg), + "Failed to get VCC regulator\n"); + + return 0; +} + +struct ssd130x_device *ssd130x_probe(struct device *dev, struct regmap *regmap) +{ + struct ssd130x_device *ssd130x; + struct backlight_device *bl; + struct drm_device *drm; + int ret; + + ssd130x = devm_drm_dev_alloc(dev, &ssd130x_drm_driver, + struct ssd130x_device, drm); + if (IS_ERR(ssd130x)) { + dev_err_probe(dev, PTR_ERR(ssd130x), + "Failed to allocate DRM device\n"); + return ssd130x; + } + + drm = &ssd130x->drm; + + ssd130x->dev = dev; + ssd130x->regmap = regmap; + ssd130x->device_info = device_get_match_data(dev); + + ssd130x_parse_properties(ssd130x); + + ret = ssd130x_get_resources(ssd130x); + if (ret) + return ERR_PTR(ret); + + bl = devm_backlight_device_register(dev, dev_name(dev), dev, ssd130x, + &ssd130xfb_bl_ops, NULL); + if (IS_ERR(bl)) { + ret = PTR_ERR(bl); + dev_err_probe(dev, ret, "Unable to register backlight device\n"); + return ERR_PTR(ret); + } + + bl->props.brightness = ssd130x->contrast; + bl->props.max_brightness = MAX_CONTRAST; + ssd130x->bl_dev = bl; + + ret = ssd130x_init_modeset(ssd130x); + if (ret) + return ERR_PTR(ret); + + ret = drm_dev_register(drm, 0); + if (ret) { + dev_err_probe(dev, ret, "DRM device register failed\n"); + return ERR_PTR(ret); + } + + drm_fbdev_generic_setup(drm, 0); + + return ssd130x; +} +EXPORT_SYMBOL_GPL(ssd130x_probe); + +int ssd130x_remove(struct ssd130x_device *ssd130x) +{ + drm_dev_unplug(&ssd130x->drm); + + return 0; +} +EXPORT_SYMBOL_GPL(ssd130x_remove); + +void ssd130x_shutdown(struct ssd130x_device *ssd130x) +{ + drm_atomic_helper_shutdown(&ssd130x->drm); +} +EXPORT_SYMBOL_GPL(ssd130x_shutdown); + +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_AUTHOR("Javier Martinez Canillas javierm@redhat.com"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/gpu/drm/solomon/ssd130x.h b/drivers/gpu/drm/solomon/ssd130x.h new file mode 100644 index 000000000000..754953b261b0 --- /dev/null +++ b/drivers/gpu/drm/solomon/ssd130x.h @@ -0,0 +1,76 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Header file for: + * DRM driver for Solomon SSD130x OLED displays + * + * Copyright 2022 Red Hat Inc. + * Authors: Javier Martinez Canillas javierm@redhat.com + * + * Based on drivers/video/fbdev/ssd1307fb.c + * Copyright 2012 Free Electrons + */ + +#ifndef __SSD1307X_H__ +#define __SSD1307X_H__ + +#include <drm/drm_drv.h> +#include <drm/drm_simple_kms_helper.h> + +#include <linux/regmap.h> + +struct ssd130x_deviceinfo { + u32 default_vcomh; + u32 default_dclk_div; + u32 default_dclk_frq; + int need_pwm; + int need_chargepump; +}; + +struct ssd130x_device { + struct drm_device drm; + struct device *dev; + struct drm_simple_display_pipe pipe; + struct drm_display_mode mode; + struct drm_connector connector; + struct i2c_client *client; + + struct regmap *regmap; + + const struct ssd130x_deviceinfo *device_info; + + unsigned area_color_enable : 1; + unsigned com_invdir : 1; + unsigned com_lrremap : 1; + unsigned com_seq : 1; + unsigned lookup_table_set : 1; + unsigned low_power : 1; + unsigned seg_remap : 1; + u32 com_offset; + u32 contrast; + u32 dclk_div; + u32 dclk_frq; + u32 height; + u8 lookup_table[4]; + u32 page_offset; + u32 col_offset; + u32 prechargep1; + u32 prechargep2; + + struct backlight_device *bl_dev; + struct pwm_device *pwm; + struct gpio_desc *reset; + struct regulator *vcc_reg; + u32 vcomh; + u32 width; + /* Cached address ranges */ + u8 col_start; + u8 col_end; + u8 page_start; + u8 page_end; +}; + +struct ssd130x_device *ssd130x_probe(struct device *dev, struct regmap *regmap); +int ssd130x_remove(struct ssd130x_device *ssd130x); +void ssd130x_shutdown(struct ssd130x_device *ssd130x); + +#endif /* __SSD1307X_H__ */