staging: fbtft: core support

This commit adds the core fbtft framework from
https://github.com/notro/fbtft.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Noralf Tronnes <notro@tronnes.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 447 insertions, 0 deletions

diff --git a/drivers/staging/fbtft/fbtft.h b/drivers/staging/fbtft/fbtft.h
new file mode 100644
index 000000000000..0dbf3f95fe78
--- /dev/null
+++ b/drivers/staging/fbtft/fbtft.h
@@ -0,0 +1,447 @@
+/*
+ * Copyright (C) 2013 Noralf Tronnes
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef __LINUX_FBTFT_H
+#define __LINUX_FBTFT_H
+
+#include <linux/fb.h>
+#include <linux/spinlock.h>
+#include <linux/spi/spi.h>
+#include <linux/platform_device.h>
+
+
+#define FBTFT_NOP		0x00
+#define FBTFT_SWRESET	0x01
+#define FBTFT_RDDID		0x04
+#define FBTFT_RDDST		0x09
+#define FBTFT_CASET		0x2A
+#define FBTFT_RASET		0x2B
+#define FBTFT_RAMWR		0x2C
+
+#define FBTFT_ONBOARD_BACKLIGHT 2
+
+#define FBTFT_GPIO_NO_MATCH		0xFFFF
+#define FBTFT_GPIO_NAME_SIZE	32
+#define FBTFT_MAX_INIT_SEQUENCE      512
+#define FBTFT_GAMMA_MAX_VALUES_TOTAL 128
+
+#define FBTFT_OF_INIT_CMD	BIT(24)
+#define FBTFT_OF_INIT_DELAY	BIT(25)
+
+/**
+ * struct fbtft_gpio - Structure that holds one pinname to gpio mapping
+ * @name: pinname (reset, dc, etc.)
+ * @gpio: GPIO number
+ *
+ */
+struct fbtft_gpio {
+	char name[FBTFT_GPIO_NAME_SIZE];
+	unsigned gpio;
+};
+
+struct fbtft_par;
+
+/**
+ * struct fbtft_ops - FBTFT operations structure
+ * @write: Writes to interface bus
+ * @read: Reads from interface bus
+ * @write_vmem: Writes video memory to display
+ * @write_reg: Writes to controller register
+ * @set_addr_win: Set the GRAM update window
+ * @reset: Reset the LCD controller
+ * @mkdirty: Marks display lines for update
+ * @update_display: Updates the display
+ * @init_display: Initializes the display
+ * @blank: Blank the display (optional)
+ * @request_gpios_match: Do pinname to gpio matching
+ * @request_gpios: Request gpios from the kernel
+ * @free_gpios: Free previously requested gpios
+ * @verify_gpios: Verify that necessary gpios is present (optional)
+ * @register_backlight: Used to register backlight device (optional)
+ * @unregister_backlight: Unregister backlight device (optional)
+ * @set_var: Configure LCD with values from variables like @rotate and @bgr
+ *           (optional)
+ * @set_gamma: Set Gamma curve (optional)
+ *
+ * Most of these operations have default functions assigned to them in
+ *     fbtft_framebuffer_alloc()
+ */
+struct fbtft_ops {
+	int (*write)(struct fbtft_par *par, void *buf, size_t len);
+	int (*read)(struct fbtft_par *par, void *buf, size_t len);
+	int (*write_vmem)(struct fbtft_par *par, size_t offset, size_t len);
+	void (*write_register)(struct fbtft_par *par, int len, ...);
+
+	void (*set_addr_win)(struct fbtft_par *par,
+		int xs, int ys, int xe, int ye);
+	void (*reset)(struct fbtft_par *par);
+	void (*mkdirty)(struct fb_info *info, int from, int to);
+	void (*update_display)(struct fbtft_par *par,
+				unsigned start_line, unsigned end_line);
+	int (*init_display)(struct fbtft_par *par);
+	int (*blank)(struct fbtft_par *par, bool on);
+
+	unsigned long (*request_gpios_match)(struct fbtft_par *par,
+		const struct fbtft_gpio *gpio);
+	int (*request_gpios)(struct fbtft_par *par);
+	int (*verify_gpios)(struct fbtft_par *par);
+
+	void (*register_backlight)(struct fbtft_par *par);
+	void (*unregister_backlight)(struct fbtft_par *par);
+
+	int (*set_var)(struct fbtft_par *par);
+	int (*set_gamma)(struct fbtft_par *par, unsigned long *curves);
+};
+
+/**
+ * struct fbtft_display - Describes the display properties
+ * @width: Width of display in pixels
+ * @height: Height of display in pixels
+ * @regwidth: LCD Controller Register width in bits
+ * @buswidth: Display interface bus width in bits
+ * @backlight: Backlight type.
+ * @fbtftops: FBTFT operations provided by driver or device (platform_data)
+ * @bpp: Bits per pixel
+ * @fps: Frames per second
+ * @txbuflen: Size of transmit buffer
+ * @init_sequence: Pointer to LCD initialization array
+ * @gamma: String representation of Gamma curve(s)
+ * @gamma_num: Number of Gamma curves
+ * @gamma_len: Number of values per Gamma curve
+ * @debug: Initial debug value
+ *
+ * This structure is not stored by FBTFT except for init_sequence.
+ */
+struct fbtft_display {
+	unsigned width;
+	unsigned height;
+	unsigned regwidth;
+	unsigned buswidth;
+	unsigned backlight;
+	struct fbtft_ops fbtftops;
+	unsigned bpp;
+	unsigned fps;
+	int txbuflen;
+	int *init_sequence;
+	char *gamma;
+	int gamma_num;
+	int gamma_len;
+	unsigned long debug;
+};
+
+/**
+ * struct fbtft_platform_data - Passes display specific data to the driver
+ * @display: Display properties
+ * @gpios: Pointer to an array of piname to gpio mappings
+ * @rotate: Display rotation angle
+ * @bgr: LCD Controller BGR bit
+ * @fps: Frames per second (this will go away, use @fps in @fbtft_display)
+ * @txbuflen: Size of transmit buffer
+ * @startbyte: When set, enables use of Startbyte in transfers
+ * @gamma: String representation of Gamma curve(s)
+ * @extra: A way to pass extra info
+ */
+struct fbtft_platform_data {
+	struct fbtft_display display;
+	const struct fbtft_gpio *gpios;
+	unsigned rotate;
+	bool bgr;
+	unsigned fps;
+	int txbuflen;
+	u8 startbyte;
+	char *gamma;
+	void *extra;
+};
+
+/**
+ * struct fbtft_par - Main FBTFT data structure
+ *
+ * This structure holds all relevant data to operate the display
+ *
+ * See sourcefile for documentation since nested structs is not
+ * supported by kernel-doc.
+ *
+ */
+/* @spi: Set if it is a SPI device
+ * @pdev: Set if it is a platform device
+ * @info: Pointer to framebuffer fb_info structure
+ * @pdata: Pointer to platform data
+ * @ssbuf: Not used
+ * @pseudo_palette: Used by fb_set_colreg()
+ * @txbuf.buf: Transmit buffer
+ * @txbuf.len: Transmit buffer length
+ * @buf: Small buffer used when writing init data over SPI
+ * @startbyte: Used by some controllers when in SPI mode.
+ *             Format: 6 bit Device id + RS bit + RW bit
+ * @fbtftops: FBTFT operations provided by driver or device (platform_data)
+ * @dirty_lock: Protects dirty_lines_start and dirty_lines_end
+ * @dirty_lines_start: Where to begin updating display
+ * @dirty_lines_end: Where to end updating display
+ * @gpio.reset: GPIO used to reset display
+ * @gpio.dc: Data/Command signal, also known as RS
+ * @gpio.rd: Read latching signal
+ * @gpio.wr: Write latching signal
+ * @gpio.latch: Bus latch signal, eg. 16->8 bit bus latch
+ * @gpio.cs: LCD Chip Select with parallel interface bus
+ * @gpio.db[16]: Parallel databus
+ * @gpio.led[16]: Led control signals
+ * @gpio.aux[16]: Auxillary signals, not used by core
+ * @init_sequence: Pointer to LCD initialization array
+ * @gamma.lock: Mutex for Gamma curve locking
+ * @gamma.curves: Pointer to Gamma curve array
+ * @gamma.num_values: Number of values per Gamma curve
+ * @gamma.num_curves: Number of Gamma curves
+ * @debug: Pointer to debug value
+ * @current_debug:
+ * @first_update_done: Used to only time the first display update
+ * @update_time: Used to calculate 'fps' in debug output
+ * @bgr: BGR mode/\n
+ * @extra: Extra info needed by driver
+ */
+struct fbtft_par {
+	struct spi_device *spi;
+	struct platform_device *pdev;
+	struct fb_info *info;
+	struct fbtft_platform_data *pdata;
+	u16 *ssbuf;
+	u32 pseudo_palette[16];
+	struct {
+		void *buf;
+		dma_addr_t dma;
+		size_t len;
+	} txbuf;
+	u8 *buf;
+	u8 startbyte;
+	struct fbtft_ops fbtftops;
+	spinlock_t dirty_lock;
+	unsigned dirty_lines_start;
+	unsigned dirty_lines_end;
+	struct {
+		int reset;
+		int dc;
+		int rd;
+		int wr;
+		int latch;
+		int cs;
+		int db[16];
+		int led[16];
+		int aux[16];
+	} gpio;
+	int *init_sequence;
+	struct {
+		struct mutex lock;
+		unsigned long *curves;
+		int num_values;
+		int num_curves;
+	} gamma;
+	unsigned long debug;
+	bool first_update_done;
+	struct timespec update_time;
+	bool bgr;
+	void *extra;
+};
+
+#define NUMARGS(...)  (sizeof((int[]){__VA_ARGS__})/sizeof(int))
+
+#define write_reg(par, ...)                                              \
+do {                                                                     \
+	par->fbtftops.write_register(par, NUMARGS(__VA_ARGS__), __VA_ARGS__); \
+} while (0)
+
+/* fbtft-core.c */
+extern void fbtft_dbg_hex(const struct device *dev,
+	int groupsize, void *buf, size_t len, const char *fmt, ...);
+extern struct fb_info *fbtft_framebuffer_alloc(struct fbtft_display *display,
+	struct device *dev);
+extern void fbtft_framebuffer_release(struct fb_info *info);
+extern int fbtft_register_framebuffer(struct fb_info *fb_info);
+extern int fbtft_unregister_framebuffer(struct fb_info *fb_info);
+extern void fbtft_register_backlight(struct fbtft_par *par);
+extern void fbtft_unregister_backlight(struct fbtft_par *par);
+extern int fbtft_init_display(struct fbtft_par *par);
+extern int fbtft_probe_common(struct fbtft_display *display,
+	struct spi_device *sdev, struct platform_device *pdev);
+extern int fbtft_remove_common(struct device *dev, struct fb_info *info);
+
+/* fbtft-io.c */
+extern int fbtft_write_spi(struct fbtft_par *par, void *buf, size_t len);
+extern int fbtft_write_spi_emulate_9(struct fbtft_par *par,
+	void *buf, size_t len);
+extern int fbtft_read_spi(struct fbtft_par *par, void *buf, size_t len);
+extern int fbtft_write_gpio8_wr(struct fbtft_par *par, void *buf, size_t len);
+extern int fbtft_write_gpio16_wr(struct fbtft_par *par, void *buf, size_t len);
+extern int fbtft_write_gpio16_wr_latched(struct fbtft_par *par,
+	void *buf, size_t len);
+
+/* fbtft-bus.c */
+extern int fbtft_write_vmem8_bus8(struct fbtft_par *par, size_t offset, size_t len);
+extern int fbtft_write_vmem16_bus16(struct fbtft_par *par, size_t offset, size_t len);
+extern int fbtft_write_vmem16_bus8(struct fbtft_par *par, size_t offset, size_t len);
+extern int fbtft_write_vmem16_bus9(struct fbtft_par *par, size_t offset, size_t len);
+extern void fbtft_write_reg8_bus8(struct fbtft_par *par, int len, ...);
+extern void fbtft_write_reg8_bus9(struct fbtft_par *par, int len, ...);
+extern void fbtft_write_reg16_bus8(struct fbtft_par *par, int len, ...);
+extern void fbtft_write_reg16_bus16(struct fbtft_par *par, int len, ...);
+
+
+#define FBTFT_REGISTER_DRIVER(_name, _compatible, _display)                \
+									   \
+static int fbtft_driver_probe_spi(struct spi_device *spi)                  \
+{                                                                          \
+	return fbtft_probe_common(_display, spi, NULL);                    \
+}                                                                          \
+									   \
+static int fbtft_driver_remove_spi(struct spi_device *spi)                 \
+{                                                                          \
+	struct fb_info *info = spi_get_drvdata(spi);                       \
+									   \
+	return fbtft_remove_common(&spi->dev, info);                       \
+}                                                                          \
+									   \
+static int fbtft_driver_probe_pdev(struct platform_device *pdev)           \
+{                                                                          \
+	return fbtft_probe_common(_display, NULL, pdev);                   \
+}                                                                          \
+									   \
+static int fbtft_driver_remove_pdev(struct platform_device *pdev)          \
+{                                                                          \
+	struct fb_info *info = platform_get_drvdata(pdev);                 \
+									   \
+	return fbtft_remove_common(&pdev->dev, info);                      \
+}                                                                          \
+									   \
+static const struct of_device_id dt_ids[] = {                              \
+        { .compatible = _compatible },                                     \
+        {},                                                                \
+};                                                                         \
+									   \
+MODULE_DEVICE_TABLE(of, dt_ids);                                           \
+									   \
+									   \
+static struct spi_driver fbtft_driver_spi_driver = {                       \
+	.driver = {                                                        \
+		.name   = _name,                                           \
+		.owner  = THIS_MODULE,                                     \
+                .of_match_table = of_match_ptr(dt_ids),                    \
+	},                                                                 \
+	.probe  = fbtft_driver_probe_spi,                                  \
+	.remove = fbtft_driver_remove_spi,                                 \
+};                                                                         \
+									   \
+static struct platform_driver fbtft_driver_platform_driver = {             \
+	.driver = {                                                        \
+		.name   = _name,                                           \
+		.owner  = THIS_MODULE,                                     \
+                .of_match_table = of_match_ptr(dt_ids),                    \
+	},                                                                 \
+	.probe  = fbtft_driver_probe_pdev,                                 \
+	.remove = fbtft_driver_remove_pdev,                                \
+};                                                                         \
+									   \
+static int __init fbtft_driver_module_init(void)                           \
+{                                                                          \
+	int ret;                                                           \
+									   \
+	ret = spi_register_driver(&fbtft_driver_spi_driver);               \
+	if (ret < 0)                                                       \
+		return ret;                                                \
+	return platform_driver_register(&fbtft_driver_platform_driver);    \
+}                                                                          \
+									   \
+static void __exit fbtft_driver_module_exit(void)                          \
+{                                                                          \
+	spi_unregister_driver(&fbtft_driver_spi_driver);                   \
+	platform_driver_unregister(&fbtft_driver_platform_driver);         \
+}                                                                          \
+									   \
+module_init(fbtft_driver_module_init);                                     \
+module_exit(fbtft_driver_module_exit);
+
+
+/* Debug macros */
+
+/* shorthand debug levels */
+#define DEBUG_LEVEL_1	DEBUG_REQUEST_GPIOS
+#define DEBUG_LEVEL_2	(DEBUG_LEVEL_1 | DEBUG_DRIVER_INIT_FUNCTIONS | DEBUG_TIME_FIRST_UPDATE)
+#define DEBUG_LEVEL_3	(DEBUG_LEVEL_2 | DEBUG_RESET | DEBUG_INIT_DISPLAY | DEBUG_BLANK | DEBUG_REQUEST_GPIOS | DEBUG_FREE_GPIOS | DEBUG_VERIFY_GPIOS | DEBUG_BACKLIGHT | DEBUG_SYSFS)
+#define DEBUG_LEVEL_4	(DEBUG_LEVEL_2 | DEBUG_FB_READ | DEBUG_FB_WRITE | DEBUG_FB_FILLRECT | DEBUG_FB_COPYAREA | DEBUG_FB_IMAGEBLIT | DEBUG_FB_BLANK)
+#define DEBUG_LEVEL_5	(DEBUG_LEVEL_3 | DEBUG_UPDATE_DISPLAY)
+#define DEBUG_LEVEL_6	(DEBUG_LEVEL_4 | DEBUG_LEVEL_5)
+#define DEBUG_LEVEL_7	0xFFFFFFFF
+
+#define DEBUG_DRIVER_INIT_FUNCTIONS (1<<3)
+#define DEBUG_TIME_FIRST_UPDATE     (1<<4)
+#define DEBUG_TIME_EACH_UPDATE      (1<<5)
+#define DEBUG_DEFERRED_IO           (1<<6)
+#define DEBUG_FBTFT_INIT_FUNCTIONS  (1<<7)
+
+/* fbops */
+#define DEBUG_FB_READ               (1<<8)
+#define DEBUG_FB_WRITE              (1<<9)
+#define DEBUG_FB_FILLRECT           (1<<10)
+#define DEBUG_FB_COPYAREA           (1<<11)
+#define DEBUG_FB_IMAGEBLIT          (1<<12)
+#define DEBUG_FB_SETCOLREG          (1<<13)
+#define DEBUG_FB_BLANK              (1<<14)
+
+#define DEBUG_SYSFS                 (1<<16)
+
+/* fbtftops */
+#define DEBUG_BACKLIGHT             (1<<17)
+#define DEBUG_READ                  (1<<18)
+#define DEBUG_WRITE                 (1<<19)
+#define DEBUG_WRITE_VMEM            (1<<20)
+#define DEBUG_WRITE_REGISTER        (1<<21)
+#define DEBUG_SET_ADDR_WIN          (1<<22)
+#define DEBUG_RESET                 (1<<23)
+#define DEBUG_MKDIRTY               (1<<24)
+#define DEBUG_UPDATE_DISPLAY        (1<<25)
+#define DEBUG_INIT_DISPLAY          (1<<26)
+#define DEBUG_BLANK                 (1<<27)
+#define DEBUG_REQUEST_GPIOS         (1<<28)
+#define DEBUG_FREE_GPIOS            (1<<29)
+#define DEBUG_REQUEST_GPIOS_MATCH   (1<<30)
+#define DEBUG_VERIFY_GPIOS          (1<<31)
+
+
+#define fbtft_init_dbg(dev, format, arg...)                  \
+do {                                                         \
+	if (unlikely((dev)->platform_data &&                 \
+	    (((struct fbtft_platform_data *)(dev)->platform_data)->display.debug & DEBUG_DRIVER_INIT_FUNCTIONS))) \
+		dev_info(dev, format, ##arg);                \
+} while (0)
+
+#define fbtft_par_dbg(level, par, format, arg...)            \
+do {                                                         \
+	if (unlikely(par->debug & level))                    \
+		dev_info(par->info->device, format, ##arg);  \
+} while (0)
+
+#define fbtft_dev_dbg(level, par, dev, format, arg...)       \
+do {                                                         \
+	if (unlikely(par->debug & level))                    \
+		dev_info(dev, format, ##arg);                \
+} while (0)
+
+#define fbtft_par_dbg_hex(level, par, dev, type, buf, num, format, arg...) \
+do {                                                                       \
+	if (unlikely(par->debug & level))                                  \
+		fbtft_dbg_hex(dev, sizeof(type), buf, num * sizeof(type), format, ##arg); \
+} while (0)
+
+#endif /* __LINUX_FBTFT_H */