video: auo_k190x: add driver for AUO-K1901 variant

This controller not only supports higher resolutions than the K1900
but concurrent updates as well. This results in a generally higher
display speed.

Signed-off-by: Heiko Stübner <heiko@sntech.de>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>

1 files changed, 251 insertions, 0 deletions

diff --git a/drivers/video/auo_k1901fb.c b/drivers/video/auo_k1901fb.c
new file mode 100644
index 000000000000..1c054c18616e
--- /dev/null
+++ b/drivers/video/auo_k1901fb.c
@@ -0,0 +1,251 @@
+/*
+ * auok190xfb.c -- FB driver for AUO-K1901 controllers
+ *
+ * Copyright (C) 2011, 2012 Heiko Stuebner <heiko@sntech.de>
+ *
+ * based on broadsheetfb.c
+ *
+ * Copyright (C) 2008, Jaya Kumar
+ *
+ * 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.
+ *
+ * Layout is based on skeletonfb.c by James Simmons and Geert Uytterhoeven.
+ *
+ * This driver is written to be used with the AUO-K1901 display controller.
+ *
+ * It is intended to be architecture independent. A board specific driver
+ * must be used to perform all the physical IO interactions.
+ *
+ * The controller supports different update modes:
+ * mode0+1 16 step gray (4bit)
+ * mode2+3 4 step gray (2bit)
+ * mode4+5 2 step gray (1bit)
+ * - mode4 is described as "without LUT"
+ * mode7 automatic selection of update mode
+ *
+ * The most interesting difference to the K1900 is the ability to do screen
+ * updates in an asynchronous fashion. Where the K1900 needs to wait for the
+ * current update to complete, the K1901 can process later updates already.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/fb.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/list.h>
+#include <linux/firmware.h>
+#include <linux/gpio.h>
+#include <linux/pm_runtime.h>
+
+#include <video/auo_k190xfb.h>
+
+#include "auo_k190x.h"
+
+/*
+ * AUO-K1901 specific commands
+ */
+
+#define AUOK1901_CMD_LUT_INTERFACE	0x0005
+#define AUOK1901_CMD_DMA_START		0x1001
+#define AUOK1901_CMD_CURSOR_START	0x1007
+#define AUOK1901_CMD_CURSOR_STOP	AUOK190X_CMD_DATA_STOP
+#define AUOK1901_CMD_DDMA_START		0x1009
+
+#define AUOK1901_INIT_GATE_PULSE_LOW	(0 << 14)
+#define AUOK1901_INIT_GATE_PULSE_HIGH	(1 << 14)
+#define AUOK1901_INIT_SINGLE_GATE	(0 << 13)
+#define AUOK1901_INIT_DOUBLE_GATE	(1 << 13)
+
+/* Bits to pixels
+ *   Mode	15-12	11-8	7-4	3-0
+ *   format2	2	T	1	T
+ *   format3	1	T	2	T
+ *   format4	T	2	T	1
+ *   format5	T	1	T	2
+ *
+ *   halftone modes:
+ *   format6	2	2	1	1
+ *   format7	1	1	2	2
+ */
+#define AUOK1901_INIT_FORMAT2		(1 << 7)
+#define AUOK1901_INIT_FORMAT3		((1 << 7) | (1 << 6))
+#define AUOK1901_INIT_FORMAT4		(1 << 8)
+#define AUOK1901_INIT_FORMAT5		((1 << 8) | (1 << 6))
+#define AUOK1901_INIT_FORMAT6		((1 << 8) | (1 << 7))
+#define AUOK1901_INIT_FORMAT7		((1 << 8) | (1 << 7) | (1 << 6))
+
+/* res[4] to bit 10
+ * res[3-0] to bits 5-2
+ */
+#define AUOK1901_INIT_RESOLUTION(_res)	(((_res & (1 << 4)) << 6) \
+					 | ((_res & 0xf) << 2))
+
+/*
+ * portrait / landscape orientation in AUOK1901_CMD_DMA_START
+ */
+#define AUOK1901_DMA_ROTATE90(_rot)		((_rot & 1) << 13)
+
+/*
+ * equivalent to 1 << 11, needs the ~ to have same rotation like K1900
+ */
+#define AUOK1901_DDMA_ROTATE180(_rot)		((~_rot & 2) << 10)
+
+static void auok1901_init(struct auok190xfb_par *par)
+{
+	struct auok190x_board *board = par->board;
+	u16 init_param = 0;
+
+	init_param |= AUOK190X_INIT_INVERSE_WHITE;
+	init_param |= AUOK190X_INIT_FORMAT0;
+	init_param |= AUOK1901_INIT_RESOLUTION(par->resolution);
+	init_param |= AUOK190X_INIT_SHIFT_LEFT;
+
+	auok190x_send_cmdargs(par, AUOK190X_CMD_INIT, 1, &init_param);
+
+	/* let the controller finish */
+	board->wait_for_rdy(par);
+}
+
+static void auok1901_update_region(struct auok190xfb_par *par, int mode,
+						u16 y1, u16 y2)
+{
+	struct device *dev = par->info->device;
+	unsigned char *buf = (unsigned char *)par->info->screen_base;
+	int xres = par->info->var.xres;
+	u16 args[5];
+
+	pm_runtime_get_sync(dev);
+
+	mutex_lock(&(par->io_lock));
+
+	/* y1 and y2 must be a multiple of 2 so drop the lowest bit */
+	y1 &= 0xfffe;
+	y2 &= 0xfffe;
+
+	dev_dbg(dev, "update (x,y,w,h,mode)=(%d,%d,%d,%d,%d)\n",
+		1, y1+1, xres, y2-y1, mode);
+
+	/* K1901: first transfer the region data */
+	args[0] = AUOK1901_DMA_ROTATE90(par->rotation) | 1;
+	args[1] = y1 + 1;
+	args[2] = xres;
+	args[3] = y2 - y1;
+	buf += y1 * xres;
+	auok190x_send_cmdargs_pixels_nowait(par, AUOK1901_CMD_DMA_START, 4,
+					    args, ((y2 - y1) * xres)/2,
+					    (u16 *) buf);
+	auok190x_send_command_nowait(par, AUOK190X_CMD_DATA_STOP);
+
+	/* K1901: second tell the controller to update the region with mode */
+	args[0] = mode | AUOK1901_DDMA_ROTATE180(par->rotation);
+	args[1] = 1;
+	args[2] = y1 + 1;
+	args[3] = xres;
+	args[4] = y2 - y1;
+	auok190x_send_cmdargs_nowait(par, AUOK1901_CMD_DDMA_START, 5, args);
+
+	par->update_cnt++;
+
+	mutex_unlock(&(par->io_lock));
+
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_put_autosuspend(dev);
+}
+
+static void auok1901fb_dpy_update_pages(struct auok190xfb_par *par,
+						u16 y1, u16 y2)
+{
+	int mode;
+
+	if (par->update_mode < 0) {
+		mode = AUOK190X_UPDATE_MODE(1);
+		par->last_mode = -1;
+	} else {
+		mode = AUOK190X_UPDATE_MODE(par->update_mode);
+		par->last_mode = par->update_mode;
+	}
+
+	if (par->flash)
+		mode |= AUOK190X_UPDATE_NONFLASH;
+
+	auok1901_update_region(par, mode, y1, y2);
+}
+
+static void auok1901fb_dpy_update(struct auok190xfb_par *par)
+{
+	int mode;
+
+	/* When doing full updates, wait for the controller to be ready
+	 * This will hopefully catch some hangs of the K1901
+	 */
+	par->board->wait_for_rdy(par);
+
+	if (par->update_mode < 0) {
+		mode = AUOK190X_UPDATE_MODE(0);
+		par->last_mode = -1;
+	} else {
+		mode = AUOK190X_UPDATE_MODE(par->update_mode);
+		par->last_mode = par->update_mode;
+	}
+
+	if (par->flash)
+		mode |= AUOK190X_UPDATE_NONFLASH;
+
+	auok1901_update_region(par, mode, 0, par->info->var.yres);
+	par->update_cnt = 0;
+}
+
+static bool auok1901fb_need_refresh(struct auok190xfb_par *par)
+{
+	return (par->update_cnt > 10);
+}
+
+static int __devinit auok1901fb_probe(struct platform_device *pdev)
+{
+	struct auok190x_init_data init;
+	struct auok190x_board *board;
+
+	/* pick up board specific routines */
+	board = pdev->dev.platform_data;
+	if (!board)
+		return -EINVAL;
+
+	/* fill temporary init struct for common init */
+	init.id = "auo_k1901fb";
+	init.board = board;
+	init.update_partial = auok1901fb_dpy_update_pages;
+	init.update_all = auok1901fb_dpy_update;
+	init.need_refresh = auok1901fb_need_refresh;
+	init.init = auok1901_init;
+
+	return auok190x_common_probe(pdev, &init);
+}
+
+static int __devexit auok1901fb_remove(struct platform_device *pdev)
+{
+	return auok190x_common_remove(pdev);
+}
+
+static struct platform_driver auok1901fb_driver = {
+	.probe	= auok1901fb_probe,
+	.remove = __devexit_p(auok1901fb_remove),
+	.driver	= {
+		.owner	= THIS_MODULE,
+		.name	= "auo_k1901fb",
+		.pm = &auok190x_pm,
+	},
+};
+module_platform_driver(auok1901fb_driver);
+
+MODULE_DESCRIPTION("framebuffer driver for the AUO-K1901 EPD controller");
+MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
+MODULE_LICENSE("GPL");