1/*
2 * drivers/video/ubicom32lcd.c
3 *	LCD initilization code
4 *
5 * (C) Copyright 2009, Ubicom, Inc.
6 *
7 * This file is part of the Ubicom32 Linux Kernel Port.
8 *
9 * The Ubicom32 Linux Kernel Port is free software: you can redistribute
10 * it and/or modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation, either version 2 of the
12 * License, or (at your option) any later version.
13 *
14 * The Ubicom32 Linux Kernel Port is distributed in the hope that it
15 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
16 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
17 * the GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with the Ubicom32 Linux Kernel Port.  If not,
21 * see <http://www.gnu.org/licenses/>.
22 */
23#include <linux/init.h>
24#include <linux/kernel.h>
25#include <linux/module.h>
26#include <linux/platform_device.h>
27#include <linux/delay.h>
28
29#include <asm/ip5000.h>
30#include <asm/gpio.h>
31#include <asm/ubicom32lcd.h>
32
33#include "ubicom32lcd.h"
34
35#define DRIVER_NAME			"ubicom32lcd"
36
37struct ubicom32lcd_data {
38	const struct ubicom32lcd_panel	*panel;
39
40	int				pin_cs;
41	int				pin_rd;
42	int				pin_rs;
43	int				pin_wr;
44	int				pin_reset;
45	struct ubicom32_io_port		*port_data;
46	int				data_shift;
47};
48
49/*
50 * ubicom32lcd_write
51 *	Performs a write cycle on the bus (assumes CS asserted, RD & WR set)
52 */
53static void ubicom32lcd_write(struct ubicom32lcd_data *ud, int command, u16 data)
54{
55	if (command) {
56		UBICOM32_GPIO_SET_PIN_LOW(ud->pin_rs);
57	} else {
58		UBICOM32_GPIO_SET_PIN_HIGH(ud->pin_rs);
59	}
60
61	asm volatile (
62		"or.4	4(%[port]), 4(%[port]), %[mask]	\n\t"
63		"not.4	%[mask], %[mask]		\n\t"
64		"and.4	8(%[port]), 8(%[port]), %[mask]	\n\t"
65		"or.4	8(%[port]), 8(%[port]), %[cmd]	\n\t"
66		:
67		: [port] "a" (ud->port_data),
68		  [mask] "d" (0xFFFF << ud->data_shift),
69		  [cmd] "d" (data << ud->data_shift)
70		: "cc"
71	);
72
73	UBICOM32_GPIO_SET_PIN_LOW(ud->pin_wr);
74
75	//ndelay(50);
76	udelay(1);
77
78	UBICOM32_GPIO_SET_PIN_HIGH(ud->pin_wr);
79
80	udelay(1);
81	//ndelay(50);
82}
83
84/*
85 * ubicom32lcd_read_data
86 *	Performs a read cycle on the bus (assumes CS asserted, RD & WR set)
87 */
88static u16 ubicom32lcd_read_data(struct ubicom32lcd_data *ud)
89{
90	u32_t data;
91
92	UBICOM32_GPIO_SET_PIN_HIGH(ud->pin_rs);
93
94	asm volatile (
95		"and.4	4(%[port]), 4(%[port]), %[mask]\n\t"
96		:
97		: [port] "a" (ud->port_data),
98		  [mask] "d" (~(0xFFFF << ud->data_shift))
99		: "cc"
100	);
101
102	UBICOM32_GPIO_SET_PIN_LOW(ud->pin_rd);
103
104	ndelay(300);
105
106	asm volatile (
107		"lsr.4	%[data], 12(%[port]), %[shamt]	\n\t"
108		"and.4	%[data], %[data], %[mask]	\n\t"
109		: [data] "=d" (data)
110		: [port] "a" (ud->port_data),
111		  [mask] "d" (0xFFFF),
112		  [shamt] "d" (ud->data_shift)
113		: "cc"
114	);
115
116	ndelay(200);
117
118	UBICOM32_GPIO_SET_PIN_HIGH(ud->pin_rd);
119
120	ndelay(500);
121
122	return data;
123}
124
125/*
126 * ubicom32lcd_execute
127 *	Executes a script for performing operations on the LCD (assumes CS set)
128 */
129static void ubicom32lcd_execute(struct ubicom32lcd_data *ud, const struct ubicom32lcd_step *script)
130{
131	while (1) {
132		switch (script->op) {
133		case LCD_STEP_CMD:
134			ubicom32lcd_write(ud, 1, script->cmd);
135			break;
136
137		case LCD_STEP_DATA:
138			ubicom32lcd_write(ud, 0, script->data);
139			break;
140
141		case LCD_STEP_CMD_DATA:
142			ubicom32lcd_write(ud, 1, script->cmd);
143			ubicom32lcd_write(ud, 0, script->data);
144			break;
145
146		case LCD_STEP_SLEEP:
147			udelay(script->data);
148			break;
149
150		case LCD_STEP_DONE:
151			return;
152		}
153		script++;
154	}
155}
156
157/*
158 * ubicom32lcd_goto
159 *	Places the gram pointer at a specific X, Y address
160 */
161static void ubicom32lcd_goto(struct ubicom32lcd_data *ud, int x, int y)
162{
163	ubicom32lcd_write(ud, 1, ud->panel->horz_reg);
164	ubicom32lcd_write(ud, 0, x);
165	ubicom32lcd_write(ud, 1, ud->panel->vert_reg);
166	ubicom32lcd_write(ud, 0, y);
167	ubicom32lcd_write(ud, 1, ud->panel->gram_reg);
168}
169
170/*
171 * ubicom32lcd_panel_init
172 *	Initializes the lcd panel.
173 */
174static int ubicom32lcd_panel_init(struct ubicom32lcd_data *ud)
175{
176	u16 id;
177
178	UBICOM32_GPIO_SET_PIN_LOW(ud->pin_reset);
179	UBICOM32_GPIO_SET_PIN_OUTPUT(ud->pin_reset);
180	UBICOM32_GPIO_ENABLE(ud->pin_reset);
181
182	asm volatile (
183		"or.4	0x50(%[port]), 0x50(%[port]), %[mask]	\n\t"
184		"not.4	%[mask], %[mask]			\n\t"
185		"and.4	0x04(%[port]), 0x04(%[port]), %[mask]	\n\t"
186		:
187		: [port] "a" (ud->port_data),
188		  [mask] "d" (0xFFFF << ud->data_shift)
189		: "cc"
190	);
191
192	UBICOM32_GPIO_SET_PIN_HIGH(ud->pin_rs);
193	UBICOM32_GPIO_SET_PIN_HIGH(ud->pin_rd);
194	UBICOM32_GPIO_SET_PIN_HIGH(ud->pin_wr);
195	UBICOM32_GPIO_SET_PIN_HIGH(ud->pin_cs);
196
197	UBICOM32_GPIO_SET_PIN_OUTPUT(ud->pin_rs);
198	UBICOM32_GPIO_SET_PIN_OUTPUT(ud->pin_rd);
199	UBICOM32_GPIO_SET_PIN_OUTPUT(ud->pin_wr);
200	UBICOM32_GPIO_SET_PIN_OUTPUT(ud->pin_cs);
201
202	UBICOM32_GPIO_ENABLE(ud->pin_rs);
203	UBICOM32_GPIO_ENABLE(ud->pin_rd);
204	UBICOM32_GPIO_ENABLE(ud->pin_wr);
205	UBICOM32_GPIO_ENABLE(ud->pin_cs);
206
207	udelay(20);
208
209	UBICOM32_GPIO_SET_PIN_HIGH(ud->pin_reset);
210
211	udelay(20);
212
213	UBICOM32_GPIO_SET_PIN_LOW(ud->pin_cs);
214
215	id = ubicom32lcd_read_data(ud);
216
217	/*
218	 * We will try to figure out what kind of panel we have if we were not told.
219	 */
220	if (!ud->panel) {
221		const struct ubicom32lcd_panel **p = ubicom32lcd_panels;
222		while (*p) {
223			if ((*p)->id && ((*p)->id == id)) {
224				break;
225			}
226			p++;
227		}
228		if (!*p) {
229			printk(KERN_WARNING DRIVER_NAME ":Could not find compatible panel, id=%x\n", id);
230			return -ENODEV;
231		}
232		ud->panel = *p;
233	}
234
235	/*
236	 * Make sure panel ID matches if we were supplied a panel type
237	 */
238	if (ud->panel->id && (ud->panel->id != id)) {
239		UBICOM32_GPIO_SET_PIN_HIGH(ud->pin_cs);
240
241		return -ENODEV;
242	}
243
244	ubicom32lcd_execute(ud, ud->panel->init_seq);
245
246	ubicom32lcd_goto(ud, 0, 0);
247
248	UBICOM32_GPIO_SET_PIN_HIGH(ud->pin_cs);
249	UBICOM32_GPIO_SET_PIN_HIGH(ud->pin_rd);
250	UBICOM32_GPIO_SET_PIN_HIGH(ud->pin_wr);
251	UBICOM32_GPIO_SET_PIN_HIGH(ud->pin_rs);
252
253	printk(KERN_INFO DRIVER_NAME ": Initialized panel %s\n", ud->panel->desc);
254
255	return 0;
256}
257
258/*
259 * ubicom32lcd_probe
260 */
261static int ubicom32lcd_probe(struct platform_device *pdev)
262{
263	const struct ubicom32lcd_platform_data *pdata = pdev->dev.platform_data;
264	struct ubicom32lcd_data *ud;
265	int retval;
266
267	/*
268	 * Allocate our private data
269	 */
270	ud = kzalloc(sizeof(struct ubicom32lcd_data), GFP_KERNEL);
271	if (!ud) {
272		return -ENOMEM;
273	}
274
275	if (pdata) {
276		ud->pin_cs = pdata->pin_cs;
277		ud->pin_rd = pdata->pin_rd;
278		ud->pin_wr = pdata->pin_wr;
279		ud->pin_rs = pdata->pin_rs;
280		ud->pin_reset = pdata->pin_reset;
281		ud->port_data = pdata->port_data;
282		ud->data_shift = pdata->data_shift;
283	} else {
284		/*
285		 * Defaults
286		 */
287		ud->pin_cs = GPIO_RD_4;
288		ud->pin_rd = GPIO_RD_5;
289		ud->pin_rs = GPIO_RD_3;
290		ud->pin_wr = GPIO_RD_2;
291		ud->pin_reset = GPIO_RD_7;
292		ud->port_data = (struct ubicom32_io_port *)RI;
293		ud->data_shift = 0;
294	}
295
296	/*
297	 * Initialize the display
298	 */
299	retval = ubicom32lcd_panel_init(ud);
300	if (retval) {
301		kfree(ud);
302		return retval;
303	}
304
305	printk(KERN_INFO DRIVER_NAME ": LCD initialized\n");
306
307	return 0;
308}
309
310/*
311 * ubicom32lcd_remove
312 */
313static int __exit ubicom32lcd_remove(struct platform_device *pdev)
314{
315	struct ubicom32lcd_data *ud = platform_get_drvdata(pdev);
316
317	kfree(ud);
318
319	return 0;
320}
321
322static struct platform_driver ubicom32lcd_driver = {
323	.probe          = ubicom32lcd_probe,
324	.remove         = ubicom32lcd_remove,
325
326	.driver = {
327		.name = DRIVER_NAME,
328		.owner = THIS_MODULE,
329	},
330
331	.remove = __exit_p(ubicom32lcd_remove),
332};
333
334static struct platform_device *ubicom32lcd_device;
335
336/*
337 * ubicom32lcd_init
338 */
339static int __init ubicom32lcd_init(void)
340{
341	int res;
342
343	res = platform_driver_register(&ubicom32lcd_driver);
344	if (res == 0) {
345		ubicom32lcd_device = platform_device_alloc(DRIVER_NAME, 0);
346		if (ubicom32lcd_device) {
347			res = platform_device_add(ubicom32lcd_device);
348		} else {
349			res = -ENOMEM;
350		}
351		if (res) {
352			platform_device_put(ubicom32lcd_device);
353			platform_driver_unregister(&ubicom32lcd_driver);
354		}
355	}
356	return res;
357}
358module_init(ubicom32lcd_init);
359
360/*
361 * ubicom32lcd_exit
362 */
363static void __exit ubicom32lcd_exit(void)
364{
365	platform_device_unregister(ubicom32lcd_device);
366	platform_driver_unregister(&ubicom32lcd_driver);
367}
368module_exit(ubicom32lcd_exit);
369
370MODULE_AUTHOR("Patrick Tjin <@ubicom.com>");
371MODULE_DESCRIPTION("Ubicom32 LCD driver");
372MODULE_LICENSE("GPL");
373