1/*
2 * am200epd.c -- Platform device for AM200 EPD kit
3 *
4 * Copyright (C) 2008, Jaya Kumar
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file COPYING in the main directory of this archive for
8 * more details.
9 *
10 * Layout is based on skeletonfb.c by James Simmons and Geert Uytterhoeven.
11 *
12 * This work was made possible by help and equipment support from E-Ink
13 * Corporation. http://support.eink.com/community
14 *
15 * This driver is written to be used with the Metronome display controller.
16 * on the AM200 EPD prototype kit/development kit with an E-Ink 800x600
17 * Vizplex EPD on a Gumstix board using the Lyre interface board.
18 *
19 */
20
21#include <linux/module.h>
22#include <linux/kernel.h>
23#include <linux/errno.h>
24#include <linux/string.h>
25#include <linux/delay.h>
26#include <linux/interrupt.h>
27#include <linux/fb.h>
28#include <linux/init.h>
29#include <linux/platform_device.h>
30#include <linux/irq.h>
31#include <linux/gpio.h>
32
33#include "pxa25x.h"
34#include "gumstix.h"
35#include <linux/platform_data/video-pxafb.h>
36
37#include "generic.h"
38
39#include <video/metronomefb.h>
40
41static unsigned int panel_type = 6;
42static struct platform_device *am200_device;
43static struct metronome_board am200_board;
44
45static struct pxafb_mode_info am200_fb_mode_9inch7 = {
46	.pixclock	= 40000,
47	.xres		= 1200,
48	.yres		= 842,
49	.bpp		= 16,
50	.hsync_len	= 2,
51	.left_margin	= 2,
52	.right_margin	= 2,
53	.vsync_len	= 1,
54	.upper_margin	= 2,
55	.lower_margin	= 25,
56	.sync		= FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
57};
58
59static struct pxafb_mode_info am200_fb_mode_8inch = {
60	.pixclock	= 40000,
61	.xres		= 1088,
62	.yres		= 791,
63	.bpp		= 16,
64	.hsync_len	= 28,
65	.left_margin	= 8,
66	.right_margin	= 30,
67	.vsync_len	= 8,
68	.upper_margin	= 10,
69	.lower_margin	= 8,
70	.sync		= FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
71};
72
73static struct pxafb_mode_info am200_fb_mode_6inch = {
74	.pixclock	= 40189,
75	.xres		= 832,
76	.yres		= 622,
77	.bpp		= 16,
78	.hsync_len	= 28,
79	.left_margin	= 34,
80	.right_margin	= 34,
81	.vsync_len	= 25,
82	.upper_margin	= 0,
83	.lower_margin	= 2,
84	.sync		= FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
85};
86
87static struct pxafb_mach_info am200_fb_info = {
88	.modes		= &am200_fb_mode_6inch,
89	.num_modes	= 1,
90	.lcd_conn	= LCD_TYPE_COLOR_TFT | LCD_PCLK_EDGE_FALL |
91			  LCD_AC_BIAS_FREQ(24),
92};
93
94/* register offsets for gpio control */
95#define LED_GPIO_PIN 51
96#define STDBY_GPIO_PIN 48
97#define RST_GPIO_PIN 49
98#define RDY_GPIO_PIN 32
99#define ERR_GPIO_PIN 17
100#define PCBPWR_GPIO_PIN 16
101static int gpios[] = { LED_GPIO_PIN , STDBY_GPIO_PIN , RST_GPIO_PIN,
102			RDY_GPIO_PIN, ERR_GPIO_PIN, PCBPWR_GPIO_PIN };
103static char *gpio_names[] = { "LED" , "STDBY" , "RST", "RDY", "ERR", "PCBPWR" };
104
105static int am200_init_gpio_regs(struct metronomefb_par *par)
106{
107	int i;
108	int err;
109
110	for (i = 0; i < ARRAY_SIZE(gpios); i++) {
111		err = gpio_request(gpios[i], gpio_names[i]);
112		if (err) {
113			dev_err(&am200_device->dev, "failed requesting "
114				"gpio %s, err=%d\n", gpio_names[i], err);
115			goto err_req_gpio;
116		}
117	}
118
119	gpio_direction_output(LED_GPIO_PIN, 0);
120	gpio_direction_output(STDBY_GPIO_PIN, 0);
121	gpio_direction_output(RST_GPIO_PIN, 0);
122
123	gpio_direction_input(RDY_GPIO_PIN);
124	gpio_direction_input(ERR_GPIO_PIN);
125
126	gpio_direction_output(PCBPWR_GPIO_PIN, 0);
127
128	return 0;
129
130err_req_gpio:
131	while (--i >= 0)
132		gpio_free(gpios[i]);
133
134	return err;
135}
136
137static void am200_cleanup(struct metronomefb_par *par)
138{
139	int i;
140
141	free_irq(PXA_GPIO_TO_IRQ(RDY_GPIO_PIN), par);
142
143	for (i = 0; i < ARRAY_SIZE(gpios); i++)
144		gpio_free(gpios[i]);
145}
146
147static int am200_share_video_mem(struct fb_info *info)
148{
149	/* rough check if this is our desired fb and not something else */
150	if ((info->var.xres != am200_fb_info.modes->xres)
151		|| (info->var.yres != am200_fb_info.modes->yres))
152		return 0;
153
154	/* we've now been notified that we have our new fb */
155	am200_board.metromem = info->screen_base;
156	am200_board.host_fbinfo = info;
157
158	/* try to refcount host drv since we are the consumer after this */
159	if (!try_module_get(info->fbops->owner))
160		return -ENODEV;
161
162	return 0;
163}
164
165static int am200_unshare_video_mem(struct fb_info *info)
166{
167	dev_dbg(&am200_device->dev, "ENTER %s\n", __func__);
168
169	if (info != am200_board.host_fbinfo)
170		return 0;
171
172	module_put(am200_board.host_fbinfo->fbops->owner);
173	return 0;
174}
175
176static int am200_fb_notifier_callback(struct notifier_block *self,
177				 unsigned long event, void *data)
178{
179	struct fb_event *evdata = data;
180	struct fb_info *info = evdata->info;
181
182	dev_dbg(&am200_device->dev, "ENTER %s\n", __func__);
183
184	if (event == FB_EVENT_FB_REGISTERED)
185		return am200_share_video_mem(info);
186	else if (event == FB_EVENT_FB_UNREGISTERED)
187		return am200_unshare_video_mem(info);
188
189	return 0;
190}
191
192static struct notifier_block am200_fb_notif = {
193	.notifier_call = am200_fb_notifier_callback,
194};
195
196/* this gets called as part of our init. these steps must be done now so
197 * that we can use pxa_set_fb_info */
198static void __init am200_presetup_fb(void)
199{
200	int fw;
201	int fh;
202	int padding_size;
203	int totalsize;
204
205	switch (panel_type) {
206	case 6:
207		am200_fb_info.modes = &am200_fb_mode_6inch;
208		break;
209	case 8:
210		am200_fb_info.modes = &am200_fb_mode_8inch;
211		break;
212	case 97:
213		am200_fb_info.modes = &am200_fb_mode_9inch7;
214		break;
215	default:
216		dev_err(&am200_device->dev, "invalid panel_type selection,"
217						" setting to 6\n");
218		am200_fb_info.modes = &am200_fb_mode_6inch;
219		break;
220	}
221
222	/* the frame buffer is divided as follows:
223	command | CRC | padding
224	16kb waveform data | CRC | padding
225	image data | CRC
226	*/
227
228	fw = am200_fb_info.modes->xres;
229	fh = am200_fb_info.modes->yres;
230
231	/* waveform must be 16k + 2 for checksum */
232	am200_board.wfm_size = roundup(16*1024 + 2, fw);
233
234	padding_size = PAGE_SIZE + (4 * fw);
235
236	/* total is 1 cmd , 1 wfm, padding and image */
237	totalsize = fw + am200_board.wfm_size + padding_size + (fw*fh);
238
239	/* save this off because we're manipulating fw after this and
240	 * we'll need it when we're ready to setup the framebuffer */
241	am200_board.fw = fw;
242	am200_board.fh = fh;
243
244	/* the reason we do this adjustment is because we want to acquire
245	 * more framebuffer memory without imposing custom awareness on the
246	 * underlying pxafb driver */
247	am200_fb_info.modes->yres = DIV_ROUND_UP(totalsize, fw);
248
249	/* we divide since we told the LCD controller we're 16bpp */
250	am200_fb_info.modes->xres /= 2;
251
252	pxa_set_fb_info(NULL, &am200_fb_info);
253
254}
255
256/* this gets called by metronomefb as part of its init, in our case, we
257 * have already completed initial framebuffer init in presetup_fb so we
258 * can just setup the fb access pointers */
259static int am200_setup_fb(struct metronomefb_par *par)
260{
261	int fw;
262	int fh;
263
264	fw = am200_board.fw;
265	fh = am200_board.fh;
266
267	/* metromem was set up by the notifier in share_video_mem so now
268	 * we can use its value to calculate the other entries */
269	par->metromem_cmd = (struct metromem_cmd *) am200_board.metromem;
270	par->metromem_wfm = am200_board.metromem + fw;
271	par->metromem_img = par->metromem_wfm + am200_board.wfm_size;
272	par->metromem_img_csum = (u16 *) (par->metromem_img + (fw * fh));
273	par->metromem_dma = am200_board.host_fbinfo->fix.smem_start;
274
275	return 0;
276}
277
278static int am200_get_panel_type(void)
279{
280	return panel_type;
281}
282
283static irqreturn_t am200_handle_irq(int irq, void *dev_id)
284{
285	struct metronomefb_par *par = dev_id;
286
287	wake_up_interruptible(&par->waitq);
288	return IRQ_HANDLED;
289}
290
291static int am200_setup_irq(struct fb_info *info)
292{
293	int ret;
294
295	ret = request_irq(PXA_GPIO_TO_IRQ(RDY_GPIO_PIN), am200_handle_irq,
296				IRQF_TRIGGER_FALLING, "AM200", info->par);
297	if (ret)
298		dev_err(&am200_device->dev, "request_irq failed: %d\n", ret);
299
300	return ret;
301}
302
303static void am200_set_rst(struct metronomefb_par *par, int state)
304{
305	gpio_set_value(RST_GPIO_PIN, state);
306}
307
308static void am200_set_stdby(struct metronomefb_par *par, int state)
309{
310	gpio_set_value(STDBY_GPIO_PIN, state);
311}
312
313static int am200_wait_event(struct metronomefb_par *par)
314{
315	return wait_event_timeout(par->waitq, gpio_get_value(RDY_GPIO_PIN), HZ);
316}
317
318static int am200_wait_event_intr(struct metronomefb_par *par)
319{
320	return wait_event_interruptible_timeout(par->waitq,
321					gpio_get_value(RDY_GPIO_PIN), HZ);
322}
323
324static struct metronome_board am200_board = {
325	.owner			= THIS_MODULE,
326	.setup_irq		= am200_setup_irq,
327	.setup_io		= am200_init_gpio_regs,
328	.setup_fb		= am200_setup_fb,
329	.set_rst		= am200_set_rst,
330	.set_stdby		= am200_set_stdby,
331	.met_wait_event		= am200_wait_event,
332	.met_wait_event_intr	= am200_wait_event_intr,
333	.get_panel_type		= am200_get_panel_type,
334	.cleanup		= am200_cleanup,
335};
336
337static unsigned long am200_pin_config[] __initdata = {
338	GPIO51_GPIO,
339	GPIO49_GPIO,
340	GPIO48_GPIO,
341	GPIO32_GPIO,
342	GPIO17_GPIO,
343	GPIO16_GPIO,
344};
345
346int __init am200_init(void)
347{
348	int ret;
349
350	/*
351	 * Before anything else, we request notification for any fb
352	 * creation events.
353	 *
354	 * FIXME: This is terrible and needs to be nuked. The notifier is used
355	 * to get at the fb base address from the boot splash fb driver, which
356	 * is then passed to metronomefb. Instaed of metronomfb or this board
357	 * support file here figuring this out on their own.
358	 *
359	 * See also the #ifdef in fbmem.c.
360	 */
361	fb_register_client(&am200_fb_notif);
362
363	pxa2xx_mfp_config(ARRAY_AND_SIZE(am200_pin_config));
364
365	/* request our platform independent driver */
366	request_module("metronomefb");
367
368	am200_device = platform_device_alloc("metronomefb", -1);
369	if (!am200_device)
370		return -ENOMEM;
371
372	/* the am200_board that will be seen by metronomefb is a copy */
373	platform_device_add_data(am200_device, &am200_board,
374					sizeof(am200_board));
375
376	/* this _add binds metronomefb to am200. metronomefb refcounts am200 */
377	ret = platform_device_add(am200_device);
378
379	if (ret) {
380		platform_device_put(am200_device);
381		fb_unregister_client(&am200_fb_notif);
382		return ret;
383	}
384
385	am200_presetup_fb();
386
387	return 0;
388}
389
390module_param(panel_type, uint, 0);
391MODULE_PARM_DESC(panel_type, "Select the panel type: 6, 8, 97");
392
393MODULE_DESCRIPTION("board driver for am200 metronome epd kit");
394MODULE_AUTHOR("Jaya Kumar");
395MODULE_LICENSE("GPL");
396