Le 19/08/2024 à 23:49, Alex Lanzano a écrit :
Add support for the monochrome Sharp Memory LCDs.
Hi, a few nitpick below, should thre be a v5. ...
+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
This comment could take only 3 lines and still be with < 80 lines. A dot could also be added at the end of the 2nd sentence.
+ */ + struct mutex tx_mutex; +};
...
+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; + + ret = spi_setup(spi); + if (ret < 0) + return dev_err_probe(&spi->dev, ret, "Failed to setup spi device\n"); + + dev = &spi->dev;
If done earlier (when dev is declared?), it could already be used in the dev_err_probe() just above?
+ 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"); + + /* + * 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(&spi->dev, "sharp,vcom-mode", &vcom_mode_str))
just dev?
+ 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; + + } 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 dev_err_probe(dev, ret, + "Failed to initialize external COM signal\n"); + } else { + return dev_err_probe(dev, -EINVAL, "Invalid value set for vcom-mode\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(&spi->dev, smd->tx_buffer_size, GFP_KERNEL);
Just dev?
+ if (!smd->tx_buffer) + return -ENOMEM; + + mutex_init(&smd->tx_mutex); + + 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; +}
... CJ