MIPI DSI bus allows to model DSI hosts and DSI devices using Linux bus. DSI host should be registered by DSI master driver. During registration DSI devices will be created according to Device Tree sub-nodes, registration based on board info will be added later. DSI host exposes operations which can be used by slave drivers to access associated devices.

Signed-off-by: Andrzej Hajda a.hajda@samsung.com Signed-off-by: Kyungmin Park kyungmin.park@samsung.com --- Hi Thierry,

This is the 3rd version of MIPI DSI bus patch. Most of changes comes from Thierry comments. The main difference is complete change of 'philosophy' behind it. In previous version DSI host could be standalone driver without DRM dependency. In the current version it should be DRM device. This change breaks my drivers so I cannot test this version of patch on live system yet.

There are few things which still bother me: - DSI mode flags - some of them seems to be too specific for my HW, - other DSI parameters, probably there should be more, like max clock, supported pixel modes,....

Regards Andrzej

drivers/gpu/drm/Kconfig | 3 + drivers/gpu/drm/Makefile | 1 + drivers/gpu/drm/drm_mipi_dsi.c | 316 +++++++++++++++++++++++++++++++++++++++++ include/drm/drm_mipi_dsi.h | 155 ++++++++++++++++++++ 4 files changed, 475 insertions(+) create mode 100644 drivers/gpu/drm/drm_mipi_dsi.c create mode 100644 include/drm/drm_mipi_dsi.h

diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig index f864275..30fb2ad 100644 --- a/drivers/gpu/drm/Kconfig +++ b/drivers/gpu/drm/Kconfig @@ -20,6 +20,9 @@ menuconfig DRM details. You should also select and configure AGP (/dev/agpgart) support if it is available for your platform.

+config DRM_MIPI_DSI + bool + config DRM_USB tristate depends on DRM diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile index cc08b84..6266c6c 100644 --- a/drivers/gpu/drm/Makefile +++ b/drivers/gpu/drm/Makefile @@ -31,6 +31,7 @@ obj-$(CONFIG_DRM_KMS_HELPER) += drm_kms_helper.o CFLAGS_drm_trace_points.o := -I$(src)

obj-$(CONFIG_DRM) += drm.o +obj-$(CONFIG_DRM_MIPI_DSI) += mipi_dsi.o obj-$(CONFIG_DRM_USB) += drm_usb.o obj-$(CONFIG_DRM_TTM) += ttm/ obj-$(CONFIG_DRM_TDFX) += tdfx/ diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c new file mode 100644 index 0000000..047e632 --- /dev/null +++ b/drivers/gpu/drm/drm_mipi_dsi.c @@ -0,0 +1,316 @@ +/* + * MIPI DSI Bus + * + * Copyright (C) 2012-2013, Samsung Electronics, Co., Ltd. + * Andrzej Hajda a.hajda@samsung.com + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sub license, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice (including the + * next paragraph) shall be included in all copies or substantial portions + * of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL + * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE + * USE OR OTHER DEALINGS IN THE SOFTWARE. + */ + +#include <drm/drm_mipi_dsi.h> + +#include <linux/device.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/pm_runtime.h> +#include <linux/slab.h> + +#include <video/mipi_display.h> + +static struct mipi_dsi_device *of_mipi_dsi_device_new(struct mipi_dsi_host *host, + struct device_node *node); + +int mipi_dsi_host_register(struct mipi_dsi_host *host) +{ + struct device_node *node; + + for_each_available_child_of_node(host->dev->of_node, node) + of_mipi_dsi_device_new(host, node); + + return 0; +} +EXPORT_SYMBOL(mipi_dsi_host_register); + +static int mipi_dsi_remove_device_fn(struct device *dev, void *priv) +{ + struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev); + + device_unregister(&dsi->dev); + + return 0; +} + +void mipi_dsi_host_unregister(struct mipi_dsi_host *host) +{ + device_for_each_child(host->dev, NULL, mipi_dsi_remove_device_fn); +} +EXPORT_SYMBOL(mipi_dsi_host_unregister); + +static int mipi_dsi_device_match(struct device *dev, struct device_driver *drv) +{ + return of_driver_match_device(dev, drv); +} + +static const struct dev_pm_ops mipi_dsi_device_pm_ops = { + .runtime_suspend = pm_generic_runtime_suspend, + .runtime_resume = pm_generic_runtime_resume, + .suspend = pm_generic_suspend, + .resume = pm_generic_resume, + .freeze = pm_generic_freeze, + .thaw = pm_generic_thaw, + .poweroff = pm_generic_poweroff, + .restore = pm_generic_restore, +}; + +static struct bus_type mipi_dsi_bus_type = { + .name = "mipi-dsi", + .match = mipi_dsi_device_match, + .pm = &mipi_dsi_device_pm_ops, +}; + +void mipi_dsi_dev_release(struct device *dev) +{ + struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev); + + kfree(dsi); +} + +static const struct device_type mipi_dsi_device_type = { + .release = mipi_dsi_dev_release, +}; + +static struct mipi_dsi_device *mipi_dsi_device_alloc(struct mipi_dsi_host *host) +{ + struct mipi_dsi_device *dsi; + + dsi = kzalloc(sizeof(*dsi), GFP_KERNEL); + if (!dsi) + return ERR_PTR(-ENOMEM); + + dsi->host = host; + dsi->dev.bus = &mipi_dsi_bus_type; + dsi->dev.parent = host->dev; + dsi->dev.type = &mipi_dsi_device_type; + + device_initialize(&dsi->dev); + + return dsi; +} + +static int mipi_dsi_device_add(struct mipi_dsi_device *dsi) +{ + struct mipi_dsi_host *host = dsi->host; + + dev_set_name(&dsi->dev, "%s.%d", dev_name(host->dev), dsi->channel); + + return device_add(&dsi->dev); +} + +static struct mipi_dsi_device *of_mipi_dsi_device_new(struct mipi_dsi_host *host, + struct device_node *node) +{ + struct mipi_dsi_device *dsi; + struct device *dev = host->dev; + int ret; + u32 reg; + + ret = of_property_read_u32(node, "reg", &reg); + if (ret) { + dev_err(dev, "device node %s has no valid reg property: %d\n", + node->full_name, ret); + return ERR_PTR(-EINVAL); + } + + if (reg > 3) { + dev_err(dev, "device node %s has invalid reg property: %u\n", + node->full_name, reg); + return ERR_PTR(-EINVAL); + } + + dsi = mipi_dsi_device_alloc(host); + if (IS_ERR(dsi)) { + dev_err(dev, "failed to allocate DSI device %s: %ld\n", + node->full_name, PTR_ERR(dsi)); + return dsi; + } + + dsi->channel = reg; + + ret = mipi_dsi_device_add(dsi); + if (ret) { + dev_err(dev, "failed to add DSI device %s: %d\n", + node->full_name, ret); + kfree(dsi); + return ERR_PTR(ret); + } + + return dsi; +} + +/** + * mipi_dsi_attach - attach a DSI device to its DSI host + * @dsi: DSI peripheral + */ +int mipi_dsi_attach(struct mipi_dsi_device *dsi) +{ + const struct mipi_dsi_host_ops *ops = dsi->host->ops; + + if (!ops || !ops->attach) + return -ENOSYS; + + return ops->attach(dsi->host, dsi); +} +EXPORT_SYMBOL(mipi_dsi_attach); + +/** + * mipi_dsi_detach - detach a DSI device from its DSI host + * @dsi: DSI peripheral + */ +int mipi_dsi_detach(struct mipi_dsi_device *dsi) +{ + const struct mipi_dsi_host_ops *ops = dsi->host->ops; + + if (!ops || !ops->detach) + return -ENOSYS; + + return ops->detach(dsi->host, dsi); +} +EXPORT_SYMBOL(mipi_dsi_detach); + +/** + * mipi_dsi_dcs_write - send DCS write command + * @dsi: DSI device + * @channel: virtual channel + * @data: pointer to the command followed by parameters + * @len: length of @data + */ +int mipi_dsi_dcs_write(struct mipi_dsi_device *dsi, unsigned int channel, + const void *data, size_t len) +{ + const struct mipi_dsi_host_ops *ops = dsi->host->ops; + struct mipi_dsi_msg msg = { + .channel = channel, + .tx_buf = data, + .tx_len = len + }; + + if (!ops || !ops->transfer) + return -ENOSYS; + + switch (len) { + case 0: + return -EINVAL; + case 1: + msg.type = MIPI_DSI_DCS_SHORT_WRITE; + break; + case 2: + msg.type = MIPI_DSI_DCS_SHORT_WRITE_PARAM; + break; + default: + msg.type = MIPI_DSI_DCS_LONG_WRITE; + } + + return ops->transfer(dsi->host, &msg); +} +EXPORT_SYMBOL(mipi_dsi_dcs_write); + +/** + * mipi_dsi_dcs_read - send DCS read request command + * @dsi: DSI device + * @channel: virtual channel + * @cmd: DCS read command + * @data: pointer to read buffer + * @len: length of @data + * + * Function returns number of read bytes or error code. + */ +ssize_t mipi_dsi_dcs_read(struct mipi_dsi_device *dsi, unsigned int channel, + u8 cmd, void *data, size_t len) +{ + const struct mipi_dsi_host_ops *ops = dsi->host->ops; + struct mipi_dsi_msg msg = { + .channel = channel, + .type = MIPI_DSI_DCS_READ, + .tx_buf = &cmd, + .tx_len = 1, + .rx_buf = data, + .rx_len = len + }; + + if (!ops || !ops->transfer) + return -ENOSYS; + + return ops->transfer(dsi->host, &msg); +} +EXPORT_SYMBOL(mipi_dsi_dcs_read); + +static int mipi_dsi_drv_probe(struct device *dev) +{ + struct mipi_dsi_driver *drv = to_mipi_dsi_driver(dev->driver); + struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev); + + return drv->probe(dsi); +} + +static int mipi_dsi_drv_remove(struct device *dev) +{ + struct mipi_dsi_driver *drv = to_mipi_dsi_driver(dev->driver); + struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev); + + return drv->remove(dsi); +} + +/** + * mipi_dsi_driver_register - register a driver for DSI devices + * @drv: DSI driver structure + */ +int mipi_dsi_driver_register(struct mipi_dsi_driver *drv) +{ + drv->driver.bus = &mipi_dsi_bus_type; + if (drv->probe) + drv->driver.probe = mipi_dsi_drv_probe; + if (drv->remove) + drv->driver.remove = mipi_dsi_drv_remove; + + return driver_register(&drv->driver); +} +EXPORT_SYMBOL(mipi_dsi_driver_register); + +/** + * mipi_dsi_driver_unregister - unregister a driver for DSI devices + * @drv: DSI driver structure + */ +void mipi_dsi_driver_unregister(struct mipi_dsi_driver *drv) +{ + driver_unregister(&drv->driver); +} +EXPORT_SYMBOL(mipi_dsi_driver_unregister); + +static int __init mipi_dsi_bus_init(void) +{ + return bus_register(&mipi_dsi_bus_type); +} + +postcore_initcall(mipi_dsi_bus_init); + +MODULE_AUTHOR("Andrzej Hajda a.hajda@samsung.com"); +MODULE_DESCRIPTION("MIPI DSI Bus"); +MODULE_LICENSE("GPL and additional rights"); diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h new file mode 100644 index 0000000..ded8bf4 --- /dev/null +++ b/include/drm/drm_mipi_dsi.h @@ -0,0 +1,155 @@ +/* + * MIPI DSI Bus + * + * Copyright (C) 2012-2013, Samsung Electronics, Co., Ltd. + * Andrzej Hajda a.hajda@samsung.com + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#ifndef __DRM_MIPI_DSI_H__ +#define __DRM_MIPI_DSI_H__ + +#include <linux/device.h> + +struct mipi_dsi_host; +struct mipi_dsi_device; + +/** + * struct mipi_dsi_msg - read/write DSI buffer + * @channel: virtual channel id + * @type: payload data type + * @tx_len: length of @tx_buf + * @tx_buf: data to be written + * @rx_len: length of @rx_buf + * @rx_buf: data to be read, or NULL + */ +struct mipi_dsi_msg { + u8 channel; + u8 type; + + size_t tx_len; + const void *tx_buf; + + size_t rx_len; + void *rx_buf; +}; + +/** + * struct mipi_dsi_host_ops - DSI bus operations + * @attach: attach DSI device to DSI host + * @detach: detach DSI device from DSI host + * @transfer: send and/or receive DSI packet, return number of received bytes, + * or error + */ +struct mipi_dsi_host_ops { + int (*attach)(struct mipi_dsi_host *host, + struct mipi_dsi_device *dsi); + int (*detach)(struct mipi_dsi_host *host, + struct mipi_dsi_device *dsi); + ssize_t (*transfer)(struct mipi_dsi_host *host, + struct mipi_dsi_msg *msg); +}; + +/** + * struct mipi_dsi_host - DSI host device + * @dev: driver model device node for this DSI host + * @ops: DSI host operations + */ +struct mipi_dsi_host { + struct device *dev; + const struct mipi_dsi_host_ops *ops; +}; + +int mipi_dsi_host_register(struct mipi_dsi_host *host); +void mipi_dsi_host_unregister(struct mipi_dsi_host *host); + +/* DSI mode flags */ + +/* video mode */ +#define DSI_MODE_VIDEO BIT(0) +/* video burst mode */ +#define DSI_MODE_VIDEO_BURST BIT(1) +/* video pulse mode */ +#define DSI_MODE_VIDEO_SYNC_PULSE BIT(2) +/* enable auto vertical count mode */ +#define DSI_MODE_VIDEO_AUTO_VERT BIT(3) +/* enable hsync-end packets in vsync-pulse and v-porch area */ +#define DSI_MODE_VIDEO_HSE BIT(4) +/* disable hfront-porch area */ +#define DSI_MODE_VIDEO_HFP BIT(5) +/* disable hback-porch area */ +#define DSI_MODE_VIDEO_HBP BIT(6) +/* disable hsync-active area */ +#define DSI_MODE_VIDEO_HSA BIT(7) +/* flush display FIFO on vsync pulse */ +#define DSI_MODE_VSYNC_FLUSH BIT(8) +/* disable EoT packets in HS mode */ +#define DSI_MODE_EOT_PACKET BIT(9) + +enum mipi_dsi_pixel_format { + DSI_FMT_RGB888, + DSI_FMT_RGB666, + DSI_FMT_RGB666_PACKED, + DSI_FMT_RGB565, +}; + +/** + * struct mipi_dsi_device - DSI peripheral device + * @host: DSI host for this peripheral + * @dev: driver model device node for this peripheral + * @channel: virtual channel assigned to the peripheral + * @format: pixel format for video mode + * @mode_flags: DSI operation mode related flags + * @data_lanes: bit-mask of active data lanes + */ +struct mipi_dsi_device { + struct mipi_dsi_host *host; + struct device dev; + + unsigned int channel; + enum mipi_dsi_pixel_format format; + unsigned long mode_flags; + unsigned char data_lanes; +}; + +#define to_mipi_dsi_device(d) container_of(d, struct mipi_dsi_device, dev) + +int mipi_dsi_attach(struct mipi_dsi_device *dsi); +int mipi_dsi_detach(struct mipi_dsi_device *dsi); +int mipi_dsi_dcs_write(struct mipi_dsi_device *dsi, unsigned int channel, + const void *data, size_t len); +ssize_t mipi_dsi_dcs_read(struct mipi_dsi_device *dsi, unsigned int channel, + u8 cmd, void *data, size_t len); + +/** + * struct mipi_dsi_driver - DSI driver + * @driver: device driver model driver + * @probe: callback for device binding + * @remove: callback for device unbinding + */ +struct mipi_dsi_driver { + struct device_driver driver; + int(*probe)(struct mipi_dsi_device *dsi); + int(*remove)(struct mipi_dsi_device *dsi); +}; + +#define to_mipi_dsi_driver(d) container_of(d, struct mipi_dsi_driver, driver) + +static inline void *mipi_dsi_get_drvdata(const struct mipi_dsi_device *dsi) +{ + return dev_get_drvdata(&dsi->dev); +} + +static inline void mipi_dsi_set_drvdata(struct mipi_dsi_device *dsi, void *data) +{ + dev_set_drvdata(&dsi->dev, data); +} + +#define module_mipi_dsi_driver(__mipi_dsi_driver) \ + module_driver(__mipi_dsi_driver, mipi_dsi_driver_register, \ + mipi_dsi_driver_unregister) + +#endif /* __DRM_MIPI_DSI__ */