2 * Copyright (C) 2011 Renesas Solutions Corp.
3 * Copyright (C) 2011 Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation; either version 2 of
8 * the License, or (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
24 /* Every register is 32bit aligned, but only 8bits in size */
25 #define ureg(name) u8 name; u8 __pad_##name##0; u16 __pad_##name##1;
36 static struct sh_i2c *base;
39 #define SH_I2C_ICCR_ICE (1 << 7)
40 #define SH_I2C_ICCR_RACK (1 << 6)
41 #define SH_I2C_ICCR_RTS (1 << 4)
42 #define SH_I2C_ICCR_BUSY (1 << 2)
43 #define SH_I2C_ICCR_SCP (1 << 0)
46 #define SH_IC_BUSY (1 << 4)
47 #define SH_IC_TACK (1 << 2)
48 #define SH_IC_WAIT (1 << 1)
49 #define SH_IC_DTE (1 << 0)
51 #ifdef CONFIG_SH_I2C_8BIT
52 /* store 8th bit of iccl and icch in ICIC register */
53 #define SH_I2C_ICIC_ICCLB8 (1 << 7)
54 #define SH_I2C_ICIC_ICCHB8 (1 << 6)
57 static u16 iccl, icch;
61 static void irq_dte(struct sh_i2c *base)
65 for (i = 0 ; i < IRQ_WAIT ; i++) {
66 if (SH_IC_DTE & readb(&base->icsr))
72 static void irq_busy(struct sh_i2c *base)
76 for (i = 0 ; i < IRQ_WAIT ; i++) {
77 if (!(SH_IC_BUSY & readb(&base->icsr)))
83 static void i2c_set_addr(struct sh_i2c *base, u8 id, u8 reg, int stop)
87 writeb(readb(&base->iccr) & ~SH_I2C_ICCR_ICE, &base->iccr);
88 writeb(readb(&base->iccr) | SH_I2C_ICCR_ICE, &base->iccr);
90 writeb(iccl & 0xff, &base->iccl);
91 writeb(icch & 0xff, &base->icch);
92 #ifdef CONFIG_SH_I2C_8BIT
94 icic |= SH_I2C_ICIC_ICCLB8;
96 icic |= SH_I2C_ICIC_ICCHB8;
98 writeb(icic, &base->icic);
100 writeb((SH_I2C_ICCR_ICE|SH_I2C_ICCR_RTS|SH_I2C_ICCR_BUSY), &base->iccr);
103 writeb(id << 1, &base->icdr);
106 writeb(reg, &base->icdr);
108 writeb((SH_I2C_ICCR_ICE|SH_I2C_ICCR_RTS), &base->iccr);
113 static void i2c_finish(struct sh_i2c *base)
115 writeb(0, &base->icsr);
116 writeb(readb(&base->iccr) & ~SH_I2C_ICCR_ICE, &base->iccr);
119 static void i2c_raw_write(struct sh_i2c *base, u8 id, u8 reg, u8 val)
121 i2c_set_addr(base, id, reg, 0);
124 writeb(val, &base->icdr);
127 writeb((SH_I2C_ICCR_ICE | SH_I2C_ICCR_RTS), &base->iccr);
134 static u8 i2c_raw_read(struct sh_i2c *base, u8 id, u8 reg)
138 #if defined(CONFIG_SH73A0)
139 i2c_set_addr(base, id, reg, 0);
141 i2c_set_addr(base, id, reg, 1);
145 writeb((SH_I2C_ICCR_ICE|SH_I2C_ICCR_RTS|SH_I2C_ICCR_BUSY), &base->iccr);
148 writeb(id << 1 | 0x01, &base->icdr);
151 writeb((SH_I2C_ICCR_ICE|SH_I2C_ICCR_SCP), &base->iccr);
154 ret = readb(&base->icdr);
156 writeb((SH_I2C_ICCR_ICE|SH_I2C_ICCR_RACK), &base->iccr);
157 readb(&base->icdr); /* Dummy read */
165 #ifdef CONFIG_I2C_MULTI_BUS
166 static unsigned int current_bus;
169 * i2c_set_bus_num - change active I2C bus
170 * @bus: bus index, zero based
171 * @returns: 0 on success, non-0 on failure
173 int i2c_set_bus_num(unsigned int bus)
175 if ((bus < 0) || (bus >= CONFIG_SYS_MAX_I2C_BUS)) {
176 printf("Bad bus: %d\n", bus);
182 base = (void *)CONFIG_SH_I2C_BASE0;
185 base = (void *)CONFIG_SH_I2C_BASE1;
187 #ifdef CONFIG_SH_I2C_BASE2
189 base = (void *)CONFIG_SH_I2C_BASE2;
192 #ifdef CONFIG_SH_I2C_BASE3
194 base = (void *)CONFIG_SH_I2C_BASE3;
197 #ifdef CONFIG_SH_I2C_BASE4
199 base = (void *)CONFIG_SH_I2C_BASE4;
211 * i2c_get_bus_num - returns index of active I2C bus
213 unsigned int i2c_get_bus_num(void)
219 #define SH_I2C_ICCL_CALC(clk, date, t_low, t_high) \
220 ((clk / rate) * (t_low / t_low + t_high))
221 #define SH_I2C_ICCH_CALC(clk, date, t_low, t_high) \
222 ((clk / rate) * (t_high / t_low + t_high))
224 void i2c_init(int speed, int slaveaddr)
228 #ifdef CONFIG_I2C_MULTI_BUS
231 base = (struct sh_i2c *)CONFIG_SH_I2C_BASE0;
234 * Calculate the value for iccl. From the data sheet:
235 * iccl = (p-clock / transfer-rate) * (L / (L + H))
236 * where L and H are the SCL low and high ratio.
238 num = CONFIG_SH_I2C_CLOCK * CONFIG_SH_I2C_DATA_LOW;
239 denom = speed * (CONFIG_SH_I2C_DATA_HIGH + CONFIG_SH_I2C_DATA_LOW);
240 tmp = num * 10 / denom;
242 iccl = (u16)((num/denom) + 1);
244 iccl = (u16)(num/denom);
246 /* Calculate the value for icch. From the data sheet:
247 icch = (p clock / transfer rate) * (H / (L + H)) */
248 num = CONFIG_SH_I2C_CLOCK * CONFIG_SH_I2C_DATA_HIGH;
249 tmp = num * 10 / denom;
251 icch = (u16)((num/denom) + 1);
253 icch = (u16)(num/denom);
257 * i2c_read: - Read multiple bytes from an i2c device
259 * The higher level routines take into account that this function is only
260 * called with len < page length of the device (see configuration file)
262 * @chip: address of the chip which is to be read
263 * @addr: i2c data address within the chip
264 * @alen: length of the i2c data address (1..2 bytes)
265 * @buffer: where to write the data
266 * @len: how much byte do we want to read
267 * @return: 0 in case of success
269 int i2c_read(u8 chip, u32 addr, int alen, u8 *buffer, int len)
272 for (i = 0 ; i < len ; i++)
273 buffer[i] = i2c_raw_read(base, chip, addr + i);
279 * i2c_write: - Write multiple bytes to an i2c device
281 * The higher level routines take into account that this function is only
282 * called with len < page length of the device (see configuration file)
284 * @chip: address of the chip which is to be written
285 * @addr: i2c data address within the chip
286 * @alen: length of the i2c data address (1..2 bytes)
287 * @buffer: where to find the data to be written
288 * @len: how much byte do we want to read
289 * @return: 0 in case of success
291 int i2c_write(u8 chip, u32 addr, int alen, u8 *buffer, int len)
294 for (i = 0; i < len ; i++)
295 i2c_raw_write(base, chip, addr + i, buffer[i]);
301 * i2c_probe: - Test if a chip answers for a given i2c address
303 * @chip: address of the chip which is searched for
304 * @return: 0 if a chip was found, -1 otherwhise
306 int i2c_probe(u8 chip)