1/*
2 * am300epd.c -- Platform device for AM300 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 * This work was made possible by help and equipment support from E-Ink
11 * Corporation. http://support.eink.com/community
12 *
13 * This driver is written to be used with the Broadsheet display controller.
14 * on the AM300 EPD prototype kit/development kit with an E-Ink 800x600
15 * Vizplex EPD on a Gumstix board using the Broadsheet interface board.
16 *
17 */
18
19#include <linux/module.h>
20#include <linux/kernel.h>
21#include <linux/errno.h>
22#include <linux/string.h>
23#include <linux/delay.h>
24#include <linux/interrupt.h>
25#include <linux/fb.h>
26#include <linux/init.h>
27#include <linux/platform_device.h>
28#include <linux/irq.h>
29#include <linux/gpio.h>
30
31#include <mach/gumstix.h>
32#include <mach/mfp-pxa25x.h>
33#include <mach/irqs.h>
34#include <linux/platform_data/video-pxafb.h>
35
36#include "generic.h"
37
38#include <video/broadsheetfb.h>
39
40static unsigned int panel_type = 6;
41static struct platform_device *am300_device;
42static struct broadsheet_board am300_board;
43
44static unsigned long am300_pin_config[] __initdata = {
45	GPIO16_GPIO,
46	GPIO17_GPIO,
47	GPIO32_GPIO,
48	GPIO48_GPIO,
49	GPIO49_GPIO,
50	GPIO51_GPIO,
51	GPIO74_GPIO,
52	GPIO75_GPIO,
53	GPIO76_GPIO,
54	GPIO77_GPIO,
55
56	/* this is the 16-bit hdb bus 58-73 */
57	GPIO58_GPIO,
58	GPIO59_GPIO,
59	GPIO60_GPIO,
60	GPIO61_GPIO,
61
62	GPIO62_GPIO,
63	GPIO63_GPIO,
64	GPIO64_GPIO,
65	GPIO65_GPIO,
66
67	GPIO66_GPIO,
68	GPIO67_GPIO,
69	GPIO68_GPIO,
70	GPIO69_GPIO,
71
72	GPIO70_GPIO,
73	GPIO71_GPIO,
74	GPIO72_GPIO,
75	GPIO73_GPIO,
76};
77
78/* register offsets for gpio control */
79#define PWR_GPIO_PIN	16
80#define CFG_GPIO_PIN	17
81#define RDY_GPIO_PIN	32
82#define DC_GPIO_PIN	48
83#define RST_GPIO_PIN	49
84#define LED_GPIO_PIN	51
85#define RD_GPIO_PIN	74
86#define WR_GPIO_PIN	75
87#define CS_GPIO_PIN	76
88#define IRQ_GPIO_PIN	77
89
90/* hdb bus */
91#define DB0_GPIO_PIN	58
92#define DB15_GPIO_PIN	73
93
94static int gpios[] = { PWR_GPIO_PIN, CFG_GPIO_PIN, RDY_GPIO_PIN, DC_GPIO_PIN,
95			RST_GPIO_PIN, RD_GPIO_PIN, WR_GPIO_PIN, CS_GPIO_PIN,
96			IRQ_GPIO_PIN, LED_GPIO_PIN };
97static char *gpio_names[] = { "PWR", "CFG", "RDY", "DC", "RST", "RD", "WR",
98				"CS", "IRQ", "LED" };
99
100static int am300_wait_event(struct broadsheetfb_par *par)
101{
102	/* todo: improve err recovery */
103	wait_event(par->waitq, gpio_get_value(RDY_GPIO_PIN));
104	return 0;
105}
106
107static int am300_init_gpio_regs(struct broadsheetfb_par *par)
108{
109	int i;
110	int err;
111	char dbname[8];
112
113	for (i = 0; i < ARRAY_SIZE(gpios); i++) {
114		err = gpio_request(gpios[i], gpio_names[i]);
115		if (err) {
116			dev_err(&am300_device->dev, "failed requesting "
117				"gpio %s, err=%d\n", gpio_names[i], err);
118			goto err_req_gpio;
119		}
120	}
121
122	/* we also need to take care of the hdb bus */
123	for (i = DB0_GPIO_PIN; i <= DB15_GPIO_PIN; i++) {
124		sprintf(dbname, "DB%d", i);
125		err = gpio_request(i, dbname);
126		if (err) {
127			dev_err(&am300_device->dev, "failed requesting "
128				"gpio %d, err=%d\n", i, err);
129			goto err_req_gpio2;
130		}
131	}
132
133	/* setup the outputs and init values */
134	gpio_direction_output(PWR_GPIO_PIN, 0);
135	gpio_direction_output(CFG_GPIO_PIN, 1);
136	gpio_direction_output(DC_GPIO_PIN, 0);
137	gpio_direction_output(RD_GPIO_PIN, 1);
138	gpio_direction_output(WR_GPIO_PIN, 1);
139	gpio_direction_output(CS_GPIO_PIN, 1);
140	gpio_direction_output(RST_GPIO_PIN, 0);
141
142	/* setup the inputs */
143	gpio_direction_input(RDY_GPIO_PIN);
144	gpio_direction_input(IRQ_GPIO_PIN);
145
146	/* start the hdb bus as an input */
147	for (i = DB0_GPIO_PIN; i <= DB15_GPIO_PIN; i++)
148		gpio_direction_output(i, 0);
149
150	/* go into command mode */
151	gpio_set_value(CFG_GPIO_PIN, 1);
152	gpio_set_value(RST_GPIO_PIN, 0);
153	msleep(10);
154	gpio_set_value(RST_GPIO_PIN, 1);
155	msleep(10);
156	am300_wait_event(par);
157
158	return 0;
159
160err_req_gpio2:
161	while (--i >= DB0_GPIO_PIN)
162		gpio_free(i);
163	i = ARRAY_SIZE(gpios);
164err_req_gpio:
165	while (--i >= 0)
166		gpio_free(gpios[i]);
167
168	return err;
169}
170
171static int am300_init_board(struct broadsheetfb_par *par)
172{
173	return am300_init_gpio_regs(par);
174}
175
176static void am300_cleanup(struct broadsheetfb_par *par)
177{
178	int i;
179
180	free_irq(PXA_GPIO_TO_IRQ(RDY_GPIO_PIN), par);
181
182	for (i = 0; i < ARRAY_SIZE(gpios); i++)
183		gpio_free(gpios[i]);
184
185	for (i = DB0_GPIO_PIN; i <= DB15_GPIO_PIN; i++)
186		gpio_free(i);
187
188}
189
190static u16 am300_get_hdb(struct broadsheetfb_par *par)
191{
192	u16 res = 0;
193	int i;
194
195	for (i = 0; i <= (DB15_GPIO_PIN - DB0_GPIO_PIN) ; i++)
196		res |= (gpio_get_value(DB0_GPIO_PIN + i)) ? (1 << i) : 0;
197
198	return res;
199}
200
201static void am300_set_hdb(struct broadsheetfb_par *par, u16 data)
202{
203	int i;
204
205	for (i = 0; i <= (DB15_GPIO_PIN - DB0_GPIO_PIN) ; i++)
206		gpio_set_value(DB0_GPIO_PIN + i, (data >> i) & 0x01);
207}
208
209
210static void am300_set_ctl(struct broadsheetfb_par *par, unsigned char bit,
211				u8 state)
212{
213	switch (bit) {
214	case BS_CS:
215		gpio_set_value(CS_GPIO_PIN, state);
216		break;
217	case BS_DC:
218		gpio_set_value(DC_GPIO_PIN, state);
219		break;
220	case BS_WR:
221		gpio_set_value(WR_GPIO_PIN, state);
222		break;
223	}
224}
225
226static int am300_get_panel_type(void)
227{
228	return panel_type;
229}
230
231static irqreturn_t am300_handle_irq(int irq, void *dev_id)
232{
233	struct broadsheetfb_par *par = dev_id;
234
235	wake_up(&par->waitq);
236	return IRQ_HANDLED;
237}
238
239static int am300_setup_irq(struct fb_info *info)
240{
241	int ret;
242	struct broadsheetfb_par *par = info->par;
243
244	ret = request_irq(PXA_GPIO_TO_IRQ(RDY_GPIO_PIN), am300_handle_irq,
245				IRQF_TRIGGER_RISING, "AM300", par);
246	if (ret)
247		dev_err(&am300_device->dev, "request_irq failed: %d\n", ret);
248
249	return ret;
250}
251
252static struct broadsheet_board am300_board = {
253	.owner			= THIS_MODULE,
254	.init			= am300_init_board,
255	.cleanup		= am300_cleanup,
256	.set_hdb		= am300_set_hdb,
257	.get_hdb		= am300_get_hdb,
258	.set_ctl		= am300_set_ctl,
259	.wait_for_rdy		= am300_wait_event,
260	.get_panel_type		= am300_get_panel_type,
261	.setup_irq		= am300_setup_irq,
262};
263
264int __init am300_init(void)
265{
266	int ret;
267
268	pxa2xx_mfp_config(ARRAY_AND_SIZE(am300_pin_config));
269
270	/* request our platform independent driver */
271	request_module("broadsheetfb");
272
273	am300_device = platform_device_alloc("broadsheetfb", -1);
274	if (!am300_device)
275		return -ENOMEM;
276
277	/* the am300_board that will be seen by broadsheetfb is a copy */
278	platform_device_add_data(am300_device, &am300_board,
279					sizeof(am300_board));
280
281	ret = platform_device_add(am300_device);
282
283	if (ret) {
284		platform_device_put(am300_device);
285		return ret;
286	}
287
288	return 0;
289}
290
291module_param(panel_type, uint, 0);
292MODULE_PARM_DESC(panel_type, "Select the panel type: 37, 6, 97");
293
294MODULE_DESCRIPTION("board driver for am300 epd kit");
295MODULE_AUTHOR("Jaya Kumar");
296MODULE_LICENSE("GPL");
297