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37#include <linux/module.h>
38#include <linux/kernel.h>
39
40#include <linux/errno.h>
41#include <linux/interrupt.h>
42
43#include <linux/init.h>
44#include <linux/delay.h>
45#include <linux/spinlock.h>
46#include <linux/io.h>
47
48#include <asm/irq.h>
49#include <mach/hardware.h>
50
51#include <mach/ssp.h>
52
53
54
55#if defined (TALK)
56#define PRINTK(f...) printk (f)
57#else
58#define PRINTK(f...) do {} while (0)
59#endif
60
61#if defined (CONFIG_ARCH_LH7A400)
62# define CPLD_SPID __REGP16(CPLD06_VIRT)
63# define CPLD_SPIC __REGP16(CPLD08_VIRT)
64# define CPLD_SPIC_CS_CODEC (1<<0)
65# define CPLD_SPIC_CS_TOUCH (1<<1)
66# define CPLD_SPIC_WRITE (0<<2)
67# define CPLD_SPIC_READ (1<<2)
68# define CPLD_SPIC_DONE (1<<3)
69# define CPLD_SPIC_LOAD (1<<4)
70# define CPLD_SPIC_START (1<<4)
71# define CPLD_SPIC_LOADED (1<<5)
72#endif
73
74#define CPLD_SPI __REGP16(CPLD0A_VIRT)
75#define CPLD_SPI_CS_EEPROM (1<<3)
76#define CPLD_SPI_SCLK (1<<2)
77#define CPLD_SPI_TX_SHIFT (1)
78#define CPLD_SPI_TX (1<<CPLD_SPI_TX_SHIFT)
79#define CPLD_SPI_RX_SHIFT (0)
80#define CPLD_SPI_RX (1<<CPLD_SPI_RX_SHIFT)
81
82
83
84#define T_SKH 1
85#define T_SKL 1
86#define T_CS 1
87#define T_CSS 1
88#define T_DIS 1
89
90
91#define P_START (1<<9)
92#define P_WRITE (1<<7)
93#define P_READ (2<<7)
94#define P_ERASE (3<<7)
95#define P_EWDS (0<<7)
96#define P_WRAL (0<<7)
97#define P_ERAL (0<<7)
98#define P_EWEN (0<<7)
99#define P_A_EWDS (0<<5)
100#define P_A_WRAL (1<<5)
101#define P_A_ERAL (2<<5)
102#define P_A_EWEN (3<<5)
103
104struct ssp_configuration {
105 int device;
106 int mode;
107 int speed;
108 int frame_size_write;
109 int frame_size_read;
110};
111
112static struct ssp_configuration ssp_configuration;
113static spinlock_t ssp_lock;
114
115static void enable_cs (void)
116{
117 switch (ssp_configuration.device) {
118 case DEVICE_EEPROM:
119 CPLD_SPI |= CPLD_SPI_CS_EEPROM;
120 break;
121 }
122 udelay (T_CSS);
123}
124
125static void disable_cs (void)
126{
127 switch (ssp_configuration.device) {
128 case DEVICE_EEPROM:
129 CPLD_SPI &= ~CPLD_SPI_CS_EEPROM;
130 break;
131 }
132 udelay (T_CS);
133}
134
135static void pulse_clock (void)
136{
137 CPLD_SPI |= CPLD_SPI_SCLK;
138 udelay (T_SKH);
139 CPLD_SPI &= ~CPLD_SPI_SCLK;
140 udelay (T_SKL);
141}
142
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150
151
152
153
154
155
156
157
158static int execute_spi_command (int v, int cwrite, int cread)
159{
160 unsigned long l = 0;
161
162#if defined (CONFIG_MACH_LPD7A400)
163
164
165
166 if ( ssp_configuration.device == DEVICE_CODEC
167 || ssp_configuration.device == DEVICE_TOUCH) {
168 int select = 0;
169
170 PRINTK ("spi(%d %d.%d) 0x%04x",
171 ssp_configuration.device, cwrite, cread,
172 v);
173#if defined (TALK)
174 if (ssp_configuration.device == DEVICE_CODEC)
175 PRINTK (" 0x%03x -> %2d", v & 0x1ff, (v >> 9) & 0x7f);
176#endif
177 PRINTK ("\n");
178
179 if (ssp_configuration.device == DEVICE_CODEC)
180 select = CPLD_SPIC_CS_CODEC;
181 if (ssp_configuration.device == DEVICE_TOUCH)
182 select = CPLD_SPIC_CS_TOUCH;
183 if (cwrite) {
184 for (cwrite = (cwrite + 7)/8; cwrite-- > 0; ) {
185 CPLD_SPID = (v >> (8*cwrite)) & 0xff;
186 CPLD_SPIC = select | CPLD_SPIC_LOAD;
187 while (!(CPLD_SPIC & CPLD_SPIC_LOADED))
188 ;
189 CPLD_SPIC = select;
190 while (!(CPLD_SPIC & CPLD_SPIC_DONE))
191 ;
192 }
193 v = 0;
194 }
195 if (cread) {
196 mdelay (2);
197 v = 0;
198 for (cread = (cread + 7)/8; cread-- > 0;) {
199 CPLD_SPID = 0;
200 CPLD_SPIC = select | CPLD_SPIC_READ
201 | CPLD_SPIC_START;
202 while (!(CPLD_SPIC & CPLD_SPIC_LOADED))
203 ;
204 CPLD_SPIC = select | CPLD_SPIC_READ;
205 while (!(CPLD_SPIC & CPLD_SPIC_DONE))
206 ;
207 v = (v << 8) | CPLD_SPID;
208 }
209 }
210 return v;
211 }
212#endif
213
214 PRINTK ("spi(%d) 0x%04x -> 0x%x\r\n", ssp_configuration.device,
215 v & 0x1ff, (v >> 9) & 0x7f);
216
217 enable_cs ();
218
219 v <<= CPLD_SPI_TX_SHIFT;
220 while (cwrite--) {
221 CPLD_SPI
222 = (CPLD_SPI & ~CPLD_SPI_TX)
223 | ((v >> cwrite) & CPLD_SPI_TX);
224 udelay (T_DIS);
225 pulse_clock ();
226 }
227
228 if (cread < 0) {
229 int delay = 10;
230 disable_cs ();
231 udelay (1);
232 enable_cs ();
233
234 l = -1;
235 do {
236 if (CPLD_SPI & CPLD_SPI_RX) {
237 l = 0;
238 break;
239 }
240 } while (udelay (1), --delay);
241 }
242 else
243
244 while (cread-- > 0) {
245 pulse_clock ();
246 l = (l<<1)
247 | (((CPLD_SPI & CPLD_SPI_RX)
248 >> CPLD_SPI_RX_SHIFT) & 0x1);
249 }
250
251 disable_cs ();
252 return l;
253}
254
255static int ssp_init (void)
256{
257 spin_lock_init (&ssp_lock);
258 memset (&ssp_configuration, 0, sizeof (ssp_configuration));
259 return 0;
260}
261
262
263
264
265
266
267
268
269
270static void ssp_chip_select (int enable)
271{
272#if defined (CONFIG_MACH_LPD7A400)
273 int select;
274
275 if (ssp_configuration.device == DEVICE_CODEC)
276 select = CPLD_SPIC_CS_CODEC;
277 else if (ssp_configuration.device == DEVICE_TOUCH)
278 select = CPLD_SPIC_CS_TOUCH;
279 else
280 return;
281
282 if (enable)
283 CPLD_SPIC = select;
284 else
285 CPLD_SPIC = 0;
286#endif
287}
288
289static void ssp_acquire (void)
290{
291 spin_lock (&ssp_lock);
292}
293
294static void ssp_release (void)
295{
296 ssp_chip_select (0);
297 spin_unlock (&ssp_lock);
298}
299
300static int ssp_configure (int device, int mode, int speed,
301 int frame_size_write, int frame_size_read)
302{
303 ssp_configuration.device = device;
304 ssp_configuration.mode = mode;
305 ssp_configuration.speed = speed;
306 ssp_configuration.frame_size_write = frame_size_write;
307 ssp_configuration.frame_size_read = frame_size_read;
308
309 return 0;
310}
311
312static int ssp_read (void)
313{
314 return execute_spi_command (0, 0, ssp_configuration.frame_size_read);
315}
316
317static int ssp_write (u16 data)
318{
319 execute_spi_command (data, ssp_configuration.frame_size_write, 0);
320 return 0;
321}
322
323static int ssp_write_read (u16 data)
324{
325 return execute_spi_command (data, ssp_configuration.frame_size_write,
326 ssp_configuration.frame_size_read);
327}
328
329struct ssp_driver lh7a40x_cpld_ssp_driver = {
330 .init = ssp_init,
331 .acquire = ssp_acquire,
332 .release = ssp_release,
333 .configure = ssp_configure,
334 .chip_select = ssp_chip_select,
335 .read = ssp_read,
336 .write = ssp_write,
337 .write_read = ssp_write_read,
338};
339
340
341MODULE_AUTHOR("Marc Singer");
342MODULE_DESCRIPTION("LPD7A40X CPLD SPI driver");
343MODULE_LICENSE("GPL");
344