Add support for the monochrome Sharp Memory LCDs. Co-developed-by: Mehdi Djait <mehdi.djait@xxxxxxxxxxx> Signed-off-by: Mehdi Djait <mehdi.djait@xxxxxxxxxxx> Signed-off-by: Alex Lanzano <lanzano.alex@xxxxxxxxx> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> --- MAINTAINERS | 6 + drivers/gpu/drm/tiny/Kconfig | 20 + drivers/gpu/drm/tiny/Makefile | 1 + drivers/gpu/drm/tiny/sharp-memory.c | 669 ++++++++++++++++++++++++++++ 4 files changed, 696 insertions(+) create mode 100644 drivers/gpu/drm/tiny/sharp-memory.c diff --git a/MAINTAINERS b/MAINTAINERS index 5432239f3c5d..f3b1a6115711 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7289,6 +7289,12 @@ S: Maintained F: Documentation/devicetree/bindings/display/panel/samsung,s6d7aa0.yaml F: drivers/gpu/drm/panel/panel-samsung-s6d7aa0.c +DRM DRIVER FOR SHARP MEMORY LCD +M: Alex Lanzano <lanzano.alex@xxxxxxxxx> +S: Maintained +F: Documentation/devicetree/bindings/display/sharp,ls010b7dh04.yaml +F: drivers/gpu/drm/tiny/sharp-memory.c + DRM DRIVER FOR SITRONIX ST7586 PANELS M: David Lechner <david@xxxxxxxxxxxxxx> S: Maintained diff --git a/drivers/gpu/drm/tiny/Kconfig b/drivers/gpu/drm/tiny/Kconfig index f6889f649bc1..bc386954faa2 100644 --- a/drivers/gpu/drm/tiny/Kconfig +++ b/drivers/gpu/drm/tiny/Kconfig @@ -186,6 +186,26 @@ config TINYDRM_REPAPER If M is selected the module will be called repaper. +config TINYDRM_SHARP_MEMORY + tristate "DRM support for Sharp Memory LCD panels" + depends on DRM && SPI + select DRM_GEM_DMA_HELPER + select DRM_KMS_HELPER + help + DRM Driver for the following Sharp Memory Panels: + * 1.00" Sharp Memory LCD (LS010B7DH04) + * 1.10" Sharp Memory LCD (LS011B7DH03) + * 1.20" Sharp Memory LCD (LS012B7DD01) + * 1.28" Sharp Memory LCD (LS013B7DH03) + * 1.26" Sharp Memory LCD (LS013B7DH05) + * 1.80" Sharp Memory LCD (LS018B7DH02) + * 2.70" Sharp Memory LCD (LS027B7DH01) + * 2.70" Sharp Memory LCD (LS027B7DH01A) + * 3.20" Sharp Memory LCD (LS032B7DD02) + * 4.40" Sharp Memory LCD (LS044Q7DH01) + + If M is selected the module will be called sharp_memory. + config TINYDRM_ST7586 tristate "DRM support for Sitronix ST7586 display panels" depends on DRM && SPI diff --git a/drivers/gpu/drm/tiny/Makefile b/drivers/gpu/drm/tiny/Makefile index 76dde89a044b..4aaf56f8707d 100644 --- a/drivers/gpu/drm/tiny/Makefile +++ b/drivers/gpu/drm/tiny/Makefile @@ -14,5 +14,6 @@ obj-$(CONFIG_TINYDRM_ILI9341) += ili9341.o obj-$(CONFIG_TINYDRM_ILI9486) += ili9486.o obj-$(CONFIG_TINYDRM_MI0283QT) += mi0283qt.o obj-$(CONFIG_TINYDRM_REPAPER) += repaper.o +obj-$(CONFIG_TINYDRM_SHARP_MEMORY) += sharp-memory.o obj-$(CONFIG_TINYDRM_ST7586) += st7586.o obj-$(CONFIG_TINYDRM_ST7735R) += st7735r.o diff --git a/drivers/gpu/drm/tiny/sharp-memory.c b/drivers/gpu/drm/tiny/sharp-memory.c new file mode 100644 index 000000000000..605f7baf6be0 --- /dev/null +++ b/drivers/gpu/drm/tiny/sharp-memory.c @@ -0,0 +1,669 @@ +// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) + +#include <drm/drm_atomic.h> +#include <drm/drm_atomic_helper.h> +#include <drm/drm_connector.h> +#include <drm/drm_damage_helper.h> +#include <drm/drm_drv.h> +#include <drm/drm_fb_dma_helper.h> +#include <drm/drm_fbdev_dma.h> +#include <drm/drm_format_helper.h> +#include <drm/drm_framebuffer.h> +#include <drm/drm_gem_atomic_helper.h> +#include <drm/drm_gem_dma_helper.h> +#include <drm/drm_gem_framebuffer_helper.h> +#include <drm/drm_managed.h> +#include <drm/drm_modes.h> +#include <drm/drm_probe_helper.h> +#include <drm/drm_rect.h> +#include <linux/bitrev.h> +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/kthread.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/pwm.h> +#include <linux/spi/spi.h> + +#define SHARP_MODE_PERIOD 8 +#define SHARP_ADDR_PERIOD 8 +#define SHARP_DUMMY_PERIOD 8 + +#define SHARP_MEMORY_DISPLAY_MAINTAIN_MODE 0 +#define SHARP_MEMORY_DISPLAY_UPDATE_MODE 1 +#define SHARP_MEMORY_DISPLAY_CLEAR_MODE 4 + +enum sharp_memory_model { + LS010B7DH04, + LS011B7DH03, + LS012B7DD01, + LS013B7DH03, + LS013B7DH05, + LS018B7DH02, + LS027B7DH01, + LS027B7DH01A, + LS032B7DD02, + LS044Q7DH01, +}; + +enum sharp_memory_vcom_mode { + SHARP_MEMORY_SOFTWARE_VCOM, + SHARP_MEMORY_EXTERNAL_VCOM, + SHARP_MEMORY_PWM_VCOM +}; + +struct sharp_memory_device { + struct drm_device drm; + struct spi_device *spi; + + const struct drm_display_mode *mode; + + struct drm_crtc crtc; + struct drm_plane plane; + struct drm_encoder encoder; + struct drm_connector connector; + + struct gpio_desc *enable_gpio; + + struct task_struct *sw_vcom_signal; + struct pwm_device *pwm_vcom_signal; + + enum sharp_memory_vcom_mode vcom_mode; + u8 vcom; + + u32 pitch; + u32 tx_buffer_size; + u8 *tx_buffer; + + /* When vcom_mode == "software" a kthread is used to periodically send a + * 'maintain display' message over spi. This mutex ensures tx_buffer access + * and spi bus usage is synchronized in this case. + */ + struct mutex tx_mutex; +}; + +static inline int sharp_memory_spi_write(struct spi_device *spi, void *buf, size_t len) +{ + /* Reverse the bit order */ + for (u8 *b = buf; b < ((u8 *)buf) + len; ++b) + *b = bitrev8(*b); + + return spi_write(spi, buf, len); +} + +static inline struct sharp_memory_device *drm_to_sharp_memory_device(struct drm_device *drm) +{ + return container_of(drm, struct sharp_memory_device, drm); +} + +DEFINE_DRM_GEM_DMA_FOPS(sharp_memory_fops); + +static const struct drm_driver sharp_memory_drm_driver = { + .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC, + .fops = &sharp_memory_fops, + DRM_GEM_DMA_DRIVER_OPS_VMAP, + .name = "sharp_memory_display", + .desc = "Sharp Display Memory LCD", + .date = "20231129", + .major = 1, + .minor = 0, +}; + +static inline void sharp_memory_set_tx_buffer_mode(u8 *buffer, u8 mode, u8 vcom) +{ + *buffer = mode | (vcom << 1); +} + +static inline void sharp_memory_set_tx_buffer_addresses(u8 *buffer, + struct drm_rect clip, + u32 pitch) +{ + for (u32 line = 0; line < clip.y2; ++line) + buffer[line * pitch] = line + 1; +} + +static void sharp_memory_set_tx_buffer_data(u8 *buffer, + struct drm_framebuffer *fb, + struct drm_rect clip, + u32 pitch, + struct drm_format_conv_state *fmtcnv_state) +{ + int ret; + struct iosys_map dst, vmap; + struct drm_gem_dma_object *dma_obj = drm_fb_dma_get_gem_obj(fb, 0); + + ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE); + if (ret) + return; + + iosys_map_set_vaddr(&dst, buffer); + iosys_map_set_vaddr(&vmap, dma_obj->vaddr); + + drm_fb_xrgb8888_to_mono(&dst, &pitch, &vmap, fb, &clip, fmtcnv_state); + + drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE); +} + +static int sharp_memory_update_display(struct sharp_memory_device *smd, + struct drm_framebuffer *fb, + struct drm_rect clip, + struct drm_format_conv_state *fmtcnv_state) +{ + int ret; + u32 pitch = smd->pitch; + u8 vcom = smd->vcom; + u8 *tx_buffer = smd->tx_buffer; + u32 tx_buffer_size = smd->tx_buffer_size; + + mutex_lock(&smd->tx_mutex); + + /* Populate the transmit buffer with frame data */ + sharp_memory_set_tx_buffer_mode(&tx_buffer[0], + SHARP_MEMORY_DISPLAY_UPDATE_MODE, vcom); + sharp_memory_set_tx_buffer_addresses(&tx_buffer[1], clip, pitch); + sharp_memory_set_tx_buffer_data(&tx_buffer[2], fb, clip, pitch, fmtcnv_state); + + ret = sharp_memory_spi_write(smd->spi, tx_buffer, tx_buffer_size); + + mutex_unlock(&smd->tx_mutex); + + return ret; +} + +static int sharp_memory_maintain_display(struct sharp_memory_device *smd) +{ + int ret; + u8 vcom = smd->vcom; + u8 *tx_buffer = smd->tx_buffer; + + mutex_lock(&smd->tx_mutex); + + sharp_memory_set_tx_buffer_mode(&tx_buffer[0], SHARP_MEMORY_DISPLAY_MAINTAIN_MODE, vcom); + tx_buffer[1] = 0; /* Write dummy data */ + ret = sharp_memory_spi_write(smd->spi, tx_buffer, 2); + + mutex_unlock(&smd->tx_mutex); + + return ret; +} + +static int sharp_memory_clear_display(struct sharp_memory_device *smd) +{ + int ret; + u8 vcom = smd->vcom; + u8 *tx_buffer = smd->tx_buffer; + + mutex_lock(&smd->tx_mutex); + + sharp_memory_set_tx_buffer_mode(&tx_buffer[0], SHARP_MEMORY_DISPLAY_CLEAR_MODE, vcom); + tx_buffer[1] = 0; /* write dummy data */ + ret = sharp_memory_spi_write(smd->spi, tx_buffer, 2); + + mutex_unlock(&smd->tx_mutex); + + return ret; +} + +static void sharp_memory_fb_dirty(struct drm_framebuffer *fb, struct drm_rect *rect, + struct drm_format_conv_state *fmtconv_state) +{ + struct drm_rect clip; + struct sharp_memory_device *smd = drm_to_sharp_memory_device(fb->dev); + + /* Always update a full line regardless of what is dirty */ + clip.x1 = 0; + clip.x2 = fb->width; + clip.y1 = rect->y1; + clip.y2 = rect->y2; + + sharp_memory_update_display(smd, fb, clip, fmtconv_state); +} + +static int sharp_memory_plane_atomic_check(struct drm_plane *plane, + struct drm_atomic_state *state) +{ + struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(state, plane); + struct sharp_memory_device *smd; + struct drm_crtc_state *crtc_state; + + smd = container_of(plane, struct sharp_memory_device, plane); + crtc_state = drm_atomic_get_new_crtc_state(state, &smd->crtc); + + return drm_atomic_helper_check_plane_state(plane_state, crtc_state, + DRM_PLANE_NO_SCALING, + DRM_PLANE_NO_SCALING, + false, false); +} + +static void sharp_memory_plane_atomic_update(struct drm_plane *plane, + struct drm_atomic_state *state) +{ + struct drm_plane_state *old_state = drm_atomic_get_old_plane_state(state, plane); + struct drm_plane_state *plane_state = plane->state; + struct drm_format_conv_state fmtcnv_state = DRM_FORMAT_CONV_STATE_INIT; + struct sharp_memory_device *smd; + struct drm_rect rect; + + smd = container_of(plane, struct sharp_memory_device, plane); + if (!smd->crtc.state->active) + return; + + if (drm_atomic_helper_damage_merged(old_state, plane_state, &rect)) + sharp_memory_fb_dirty(plane_state->fb, &rect, &fmtcnv_state); + + drm_format_conv_state_release(&fmtcnv_state); +} + +static const struct drm_plane_helper_funcs sharp_memory_plane_helper_funcs = { + .prepare_fb = drm_gem_plane_helper_prepare_fb, + .atomic_check = sharp_memory_plane_atomic_check, + .atomic_update = sharp_memory_plane_atomic_update, +}; + +static bool sharp_memory_format_mod_supported(struct drm_plane *plane, + u32 format, + u64 modifier) +{ + return modifier == DRM_FORMAT_MOD_LINEAR; +} + +static const struct drm_plane_funcs sharp_memory_plane_funcs = { + .update_plane = drm_atomic_helper_update_plane, + .disable_plane = drm_atomic_helper_disable_plane, + .destroy = drm_plane_cleanup, + .reset = drm_atomic_helper_plane_reset, + .atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state, + .atomic_destroy_state = drm_atomic_helper_plane_destroy_state, + .format_mod_supported = sharp_memory_format_mod_supported, +}; + +static enum drm_mode_status sharp_memory_crtc_mode_valid(struct drm_crtc *crtc, + const struct drm_display_mode *mode) +{ + struct sharp_memory_device *smd = drm_to_sharp_memory_device(crtc->dev); + + return drm_crtc_helper_mode_valid_fixed(crtc, mode, smd->mode); +} + +static int sharp_memory_crtc_check(struct drm_crtc *crtc, + struct drm_atomic_state *state) +{ + struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state, crtc); + int ret; + + if (!crtc_state->enable) + goto out; + + ret = drm_atomic_helper_check_crtc_primary_plane(crtc_state); + if (ret) + return ret; + +out: + return drm_atomic_add_affected_planes(state, crtc); +} + +static int sharp_memory_sw_vcom_signal_thread(void *data) +{ + struct sharp_memory_device *smd = data; + + while (!kthread_should_stop()) { + smd->vcom ^= 1; /* Toggle vcom */ + sharp_memory_maintain_display(smd); + msleep(1000); + } + + return 0; +} + +static void sharp_memory_crtc_enable(struct drm_crtc *crtc, + struct drm_atomic_state *state) +{ + struct sharp_memory_device *smd = drm_to_sharp_memory_device(crtc->dev); + + sharp_memory_clear_display(smd); + + if (smd->enable_gpio) + gpiod_set_value(smd->enable_gpio, 1); +} + +static void sharp_memory_crtc_disable(struct drm_crtc *crtc, + struct drm_atomic_state *state) +{ + struct sharp_memory_device *smd = drm_to_sharp_memory_device(crtc->dev); + + sharp_memory_clear_display(smd); + + if (smd->enable_gpio) + gpiod_set_value(smd->enable_gpio, 0); +} + +static const struct drm_crtc_helper_funcs sharp_memory_crtc_helper_funcs = { + .mode_valid = sharp_memory_crtc_mode_valid, + .atomic_check = sharp_memory_crtc_check, + .atomic_enable = sharp_memory_crtc_enable, + .atomic_disable = sharp_memory_crtc_disable, +}; + +static const struct drm_crtc_funcs sharp_memory_crtc_funcs = { + .reset = drm_atomic_helper_crtc_reset, + .destroy = drm_crtc_cleanup, + .set_config = drm_atomic_helper_set_config, + .page_flip = drm_atomic_helper_page_flip, + .atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state, + .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state, +}; + +static const struct drm_encoder_funcs sharp_memory_encoder_funcs = { + .destroy = drm_encoder_cleanup, +}; + +static int sharp_memory_connector_get_modes(struct drm_connector *connector) +{ + struct sharp_memory_device *smd = drm_to_sharp_memory_device(connector->dev); + + return drm_connector_helper_get_modes_fixed(connector, smd->mode); +} + +static const struct drm_connector_helper_funcs sharp_memory_connector_hfuncs = { + .get_modes = sharp_memory_connector_get_modes, +}; + +static const struct drm_connector_funcs sharp_memory_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 sharp_memory_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 struct drm_display_mode sharp_memory_ls010b7dh04_mode = { + DRM_SIMPLE_MODE(128, 128, 18, 18), +}; + +static const struct drm_display_mode sharp_memory_ls011b7dh03_mode = { + DRM_SIMPLE_MODE(160, 68, 25, 10), +}; + +static const struct drm_display_mode sharp_memory_ls012b7dd01_mode = { + DRM_SIMPLE_MODE(184, 38, 29, 6), +}; + +static const struct drm_display_mode sharp_memory_ls013b7dh03_mode = { + DRM_SIMPLE_MODE(128, 128, 23, 23), +}; + +static const struct drm_display_mode sharp_memory_ls013b7dh05_mode = { + DRM_SIMPLE_MODE(144, 168, 20, 24), +}; + +static const struct drm_display_mode sharp_memory_ls018b7dh02_mode = { + DRM_SIMPLE_MODE(230, 303, 27, 36), +}; + +static const struct drm_display_mode sharp_memory_ls027b7dh01_mode = { + DRM_SIMPLE_MODE(400, 240, 58, 35), +}; + +static const struct drm_display_mode sharp_memory_ls032b7dd02_mode = { + DRM_SIMPLE_MODE(336, 536, 42, 68), +}; + +static const struct drm_display_mode sharp_memory_ls044q7dh01_mode = { + DRM_SIMPLE_MODE(320, 240, 89, 67), +}; + +static const struct spi_device_id sharp_memory_ids[] = { + {"ls010b7dh04", (kernel_ulong_t)&sharp_memory_ls010b7dh04_mode}, + {"ls011b7dh03", (kernel_ulong_t)&sharp_memory_ls011b7dh03_mode}, + {"ls012b7dd01", (kernel_ulong_t)&sharp_memory_ls012b7dd01_mode}, + {"ls013b7dh03", (kernel_ulong_t)&sharp_memory_ls013b7dh03_mode}, + {"ls013b7dh05", (kernel_ulong_t)&sharp_memory_ls013b7dh05_mode}, + {"ls018b7dh02", (kernel_ulong_t)&sharp_memory_ls018b7dh02_mode}, + {"ls027b7dh01", (kernel_ulong_t)&sharp_memory_ls027b7dh01_mode}, + {"ls027b7dh01a", (kernel_ulong_t)&sharp_memory_ls027b7dh01_mode}, + {"ls032b7dd02", (kernel_ulong_t)&sharp_memory_ls032b7dd02_mode}, + {"ls044q7dh01", (kernel_ulong_t)&sharp_memory_ls044q7dh01_mode}, + {}, +}; +MODULE_DEVICE_TABLE(spi, sharp_memory_ids); + +static const struct of_device_id sharp_memory_of_match[] = { + {.compatible = "sharp,ls010b7dh04", &sharp_memory_ls010b7dh04_mode}, + {.compatible = "sharp,ls011b7dh03", &sharp_memory_ls011b7dh03_mode}, + {.compatible = "sharp,ls012b7dd01", &sharp_memory_ls012b7dd01_mode}, + {.compatible = "sharp,ls013b7dh03", &sharp_memory_ls013b7dh03_mode}, + {.compatible = "sharp,ls013b7dh05", &sharp_memory_ls013b7dh05_mode}, + {.compatible = "sharp,ls018b7dh02", &sharp_memory_ls018b7dh02_mode}, + {.compatible = "sharp,ls027b7dh01", &sharp_memory_ls027b7dh01_mode}, + {.compatible = "sharp,ls027b7dh01a", &sharp_memory_ls027b7dh01_mode}, + {.compatible = "sharp,ls032b7dd02", &sharp_memory_ls032b7dd02_mode}, + {.compatible = "sharp,ls044q7dh01", &sharp_memory_ls044q7dh01_mode}, + {}, +}; +MODULE_DEVICE_TABLE(of, sharp_memory_of_match); + +static const u32 sharp_memory_formats[] = { + DRM_FORMAT_XRGB8888, +}; + +static int sharp_memory_pipe_init(struct drm_device *dev, + struct sharp_memory_device *smd, + const u32 *formats, unsigned int format_count, + const u64 *format_modifiers) +{ + int ret; + struct drm_encoder *encoder = &smd->encoder; + struct drm_plane *plane = &smd->plane; + struct drm_crtc *crtc = &smd->crtc; + struct drm_connector *connector = &smd->connector; + + drm_plane_helper_add(plane, &sharp_memory_plane_helper_funcs); + ret = drm_universal_plane_init(dev, plane, 0, + &sharp_memory_plane_funcs, + formats, format_count, + format_modifiers, + DRM_PLANE_TYPE_PRIMARY, NULL); + if (ret) + return ret; + + drm_crtc_helper_add(crtc, &sharp_memory_crtc_helper_funcs); + ret = drm_crtc_init_with_planes(dev, crtc, plane, NULL, + &sharp_memory_crtc_funcs, NULL); + if (ret) + return ret; + + encoder->possible_crtcs = drm_crtc_mask(crtc); + ret = drm_encoder_init(dev, encoder, &sharp_memory_encoder_funcs, + DRM_MODE_ENCODER_NONE, NULL); + if (ret) + return ret; + + ret = drm_connector_init(&smd->drm, &smd->connector, + &sharp_memory_connector_funcs, + DRM_MODE_CONNECTOR_SPI); + if (ret) + return ret; + + drm_connector_helper_add(&smd->connector, + &sharp_memory_connector_hfuncs); + + return drm_connector_attach_encoder(connector, encoder); +} + +static int sharp_memory_init_pwm_vcom_signal(struct sharp_memory_device *smd) +{ + int ret; + struct device *dev = &smd->spi->dev; + struct pwm_state pwm_state; + + smd->pwm_vcom_signal = devm_pwm_get(dev, NULL); + if (IS_ERR(smd->pwm_vcom_signal)) + return dev_err_probe(dev, PTR_ERR(smd->pwm_vcom_signal), + "Could not get pwm device\n"); + + pwm_init_state(smd->pwm_vcom_signal, &pwm_state); + pwm_set_relative_duty_cycle(&pwm_state, 1, 10); + pwm_state.enabled = true; + ret = pwm_apply_might_sleep(smd->pwm_vcom_signal, &pwm_state); + if (ret) + return dev_err_probe(dev, -EINVAL, "Could not apply pwm state\n"); + + return 0; +} + +static int sharp_memory_probe(struct spi_device *spi) +{ + int ret; + struct device *dev; + struct sharp_memory_device *smd; + struct drm_device *drm; + const char *vcom_mode_str; + + dev = &spi->dev; + + ret = spi_setup(spi); + if (ret < 0) + return dev_err_probe(dev, ret, "Failed to setup spi device\n"); + + if (!dev->coherent_dma_mask) { + ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32)); + if (ret) + return dev_err_probe(dev, ret, "Failed to set dma mask\n"); + } + + smd = devm_drm_dev_alloc(dev, &sharp_memory_drm_driver, + struct sharp_memory_device, drm); + if (!smd) + return -ENOMEM; + + spi_set_drvdata(spi, smd); + + smd->spi = spi; + drm = &smd->drm; + ret = drmm_mode_config_init(drm); + if (ret) + return dev_err_probe(dev, ret, "Failed to initialize drm config\n"); + + smd->enable_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_HIGH); + if (!smd->enable_gpio) + dev_warn(dev, "Enable gpio not defined\n"); + + drm->mode_config.funcs = &sharp_memory_mode_config_funcs; + smd->mode = spi_get_device_match_data(spi); + + smd->pitch = (SHARP_ADDR_PERIOD + smd->mode->hdisplay + SHARP_DUMMY_PERIOD) / 8; + smd->tx_buffer_size = (SHARP_MODE_PERIOD + + (SHARP_ADDR_PERIOD + (smd->mode->hdisplay) + SHARP_DUMMY_PERIOD) * + smd->mode->vdisplay) / 8; + + smd->tx_buffer = devm_kzalloc(dev, smd->tx_buffer_size, GFP_KERNEL); + if (!smd->tx_buffer) + return -ENOMEM; + + mutex_init(&smd->tx_mutex); + + /* + * VCOM is a signal that prevents DC bias from being built up in + * the panel resulting in pixels being forever stuck in one state. + * + * This driver supports three different methods to generate this + * signal depending on EXTMODE pin: + * + * software (EXTMODE = L) - This mode uses a kthread to + * periodically send a "maintain display" message to the display, + * toggling the vcom bit on and off with each message + * + * external (EXTMODE = H) - This mode relies on an external + * clock to generate the signal on the EXTCOMM pin + * + * pwm (EXTMODE = H) - This mode uses a pwm device to generate + * the signal on the EXTCOMM pin + * + */ + if (device_property_read_string(dev, "sharp,vcom-mode", &vcom_mode_str)) + return dev_err_probe(dev, -EINVAL, + "Unable to find sharp,vcom-mode node in device tree\n"); + + if (!strcmp("software", vcom_mode_str)) { + smd->vcom_mode = SHARP_MEMORY_SOFTWARE_VCOM; + smd->sw_vcom_signal = kthread_run(sharp_memory_sw_vcom_signal_thread, + smd, "sw_vcom_signal"); + + } else if (!strcmp("external", vcom_mode_str)) { + smd->vcom_mode = SHARP_MEMORY_EXTERNAL_VCOM; + + } else if (!strcmp("pwm", vcom_mode_str)) { + smd->vcom_mode = SHARP_MEMORY_PWM_VCOM; + ret = sharp_memory_init_pwm_vcom_signal(smd); + if (ret) + return ret; + } else { + return dev_err_probe(dev, -EINVAL, "Invalid value set for vcom-mode\n"); + } + + drm->mode_config.min_width = smd->mode->hdisplay; + drm->mode_config.max_width = smd->mode->hdisplay; + drm->mode_config.min_height = smd->mode->vdisplay; + drm->mode_config.max_height = smd->mode->vdisplay; + + ret = sharp_memory_pipe_init(drm, smd, sharp_memory_formats, + ARRAY_SIZE(sharp_memory_formats), + NULL); + if (ret) + return dev_err_probe(dev, ret, "Failed to initialize display pipeline.\n"); + + drm_plane_enable_fb_damage_clips(&smd->plane); + drm_mode_config_reset(drm); + + ret = drm_dev_register(drm, 0); + if (ret) + return dev_err_probe(dev, ret, "Failed to register drm device.\n"); + + drm_fbdev_dma_setup(drm, 0); + + return 0; +} + +static void sharp_memory_remove(struct spi_device *spi) +{ + struct sharp_memory_device *smd = spi_get_drvdata(spi); + + drm_dev_unplug(&smd->drm); + drm_atomic_helper_shutdown(&smd->drm); + + switch (smd->vcom_mode) { + case SHARP_MEMORY_SOFTWARE_VCOM: + kthread_stop(smd->sw_vcom_signal); + break; + + case SHARP_MEMORY_EXTERNAL_VCOM: + break; + + case SHARP_MEMORY_PWM_VCOM: + pwm_disable(smd->pwm_vcom_signal); + break; + } +} + +static struct spi_driver sharp_memory_spi_driver = { + .driver = { + .name = "sharp_memory", + .of_match_table = sharp_memory_of_match, + }, + .probe = sharp_memory_probe, + .remove = sharp_memory_remove, + .id_table = sharp_memory_ids, +}; +module_spi_driver(sharp_memory_spi_driver); + +MODULE_AUTHOR("Alex Lanzano <lanzano.alex@xxxxxxxxx>"); +MODULE_DESCRIPTION("SPI Protocol driver for the sharp_memory display"); +MODULE_LICENSE("GPL"); -- 2.46.2