target/linux/ramips/patches-4.3/0045-i2c-add-mt7621-driver.patch

   1 From d5c54ff3d1db0a4348fa04d8e78f3bf6063e3afc Mon Sep 17 00:00:00 2001
   2 From: John Crispin <blogic@openwrt.org>
   3 Date: Mon, 7 Dec 2015 17:21:27 +0100
   4 Subject: [PATCH 45/53] i2c: add mt7621 driver
   5
   6 Signed-off-by: John Crispin <blogic@openwrt.org>
   7 ---
   8  drivers/i2c/busses/Kconfig      |    4 +
   9  drivers/i2c/busses/Makefile     |    1 +
  10  drivers/i2c/busses/i2c-mt7621.c |  303 +++++++++++++++++++++++++++++++++++++++
  11  3 files changed, 308 insertions(+)
  12  create mode 100644 drivers/i2c/busses/i2c-mt7621.c
  13
  14 diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
  15 index 53d565b..073bfe3 100644
  16 --- a/drivers/i2c/busses/Kconfig
  17 +++ b/drivers/i2c/busses/Kconfig
  18 @@ -807,6 +807,10 @@ config I2C_RALINK
  19         tristate "Ralink I2C Controller"
  20         select OF_I2C
  21
  22 +config I2C_MT7621
  23 +       tristate "MT7621 I2C Controller"
  24 +       select OF_I2C
  25 +
  26  config HAVE_S3C2410_I2C
  27         bool
  28         help
  29 diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
  30 index 2edd32c..764e16e 100644
  31 --- a/drivers/i2c/busses/Makefile
  32 +++ b/drivers/i2c/busses/Makefile
  33 @@ -76,6 +76,7 @@ obj-$(CONFIG_I2C_PUV3)                += i2c-puv3.o
  34  obj-$(CONFIG_I2C_PXA)          += i2c-pxa.o
  35  obj-$(CONFIG_I2C_PXA_PCI)      += i2c-pxa-pci.o
  36  obj-$(CONFIG_I2C_RALINK)       += i2c-ralink.o
  37 +obj-$(CONFIG_I2C_MT7621)       += i2c-mt7621.o
  38  obj-$(CONFIG_I2C_QUP)          += i2c-qup.o
  39  obj-$(CONFIG_I2C_RIIC)         += i2c-riic.o
  40  obj-$(CONFIG_I2C_RK3X)         += i2c-rk3x.o
  41 diff --git a/drivers/i2c/busses/i2c-mt7621.c b/drivers/i2c/busses/i2c-mt7621.c
  42 new file mode 100644
  43 index 0000000..646ca40
  44 --- /dev/null
  45 +++ b/drivers/i2c/busses/i2c-mt7621.c
  46 @@ -0,0 +1,303 @@
  47 +/*
  48 + * drivers/i2c/busses/i2c-mt7621.c
  49 + *
  50 + * Copyright (C) 2013 Steven Liu <steven_liu@mediatek.com>
  51 + *
  52 + * Improve driver for i2cdetect from i2c-tools to detect i2c devices on the bus.
  53 + * (C) 2014 Sittisak <sittisaks@hotmail.com>
  54 + *
  55 + * This software is licensed under the terms of the GNU General Public
  56 + * License version 2, as published by the Free Software Foundation, and
  57 + * may be copied, distributed, and modified under those terms.
  58 + *
  59 + * This program is distributed in the hope that it will be useful,
  60 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
  61 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  62 + * GNU General Public License for more details.
  63 + *
  64 + */
  65 +
  66 +#include <linux/interrupt.h>
  67 +#include <linux/kernel.h>
  68 +#include <linux/module.h>
  69 +#include <linux/reset.h>
  70 +#include <linux/delay.h>
  71 +#include <linux/slab.h>
  72 +#include <linux/init.h>
  73 +#include <linux/errno.h>
  74 +#include <linux/platform_device.h>
  75 +#include <linux/i2c.h>
  76 +#include <linux/io.h>
  77 +#include <linux/err.h>
  78 +
  79 +#include <asm/mach-ralink/ralink_regs.h>
  80 +
  81 +#define REG_CONFIG_REG                       0x00
  82 +#define REG_CLKDIV_REG                       0x04
  83 +#define REG_DEVADDR_REG                      0x08
  84 +#define REG_ADDR_REG                         0x0C
  85 +#define REG_DATAOUT_REG                      0x10
  86 +#define REG_DATAIN_REG                       0x14
  87 +#define REG_STATUS_REG                       0x18
  88 +#define REG_STARTXFR_REG                     0x1C
  89 +#define REG_BYTECNT_REG                      0x20
  90 +#define REG_SM0_IS_AUTOMODE                  0x28
  91 +#define REG_SM0CTL0                          0x40
  92 +
  93 +
  94 +#define I2C_STARTERR                         0x10
  95 +#define I2C_ACKERR                           0x08
  96 +#define I2C_DATARDY                          0x04
  97 +#define I2C_SDOEMPTY                         0x02
  98 +#define I2C_BUSY                             0x01
  99 +
 100 +/* I2C_CFG register bit field */
 101 +#define I2C_CFG_ADDRLEN_8                    (7<<5)    /* 8 bits */
 102 +#define I2C_CFG_DEVADLEN_7                   (6<<2)
 103 +#define I2C_CFG_ADDRDIS                      BIT(1)
 104 +#define I2C_CFG_DEVADDIS                     BIT(0)
 105 +
 106 +#define I2C_CFG_DEFAULT        (I2C_CFG_ADDRLEN_8 | \
 107 +               I2C_CFG_DEVADLEN_7 | \
 108 +               I2C_CFG_ADDRDIS)
 109 +
 110 +#define I2C_RETRY                            0x1000
 111 +
 112 +#define CLKDIV_VALUE                         333
 113 +#define i2c_busy_loop                        (CLKDIV_VALUE*30)
 114 +
 115 +#define READ_CMD                             0x01
 116 +#define WRITE_CMD                            0x00
 117 +#define READ_BLOCK                           16
 118 +
 119 +#define SM0_ODRAIN                           BIT(31)
 120 +#define SM0_VSYNC_MODE                       BIT(28)
 121 +#define SM0_CLK_DIV                          (CLKDIV_VALUE << 16)
 122 +#define SM0_WAIT_LEVEL                       BIT(6)
 123 +#define SM0_EN                               BIT(1)
 124 +
 125 +#define SM0_CFG_DEFUALT (SM0_ODRAIN | SM0_VSYNC_MODE | \
 126 +                        SM0_CLK_DIV | SM0_WAIT_LEVEL | \
 127 +                        SM0_EN)
 128 +/***********************************************************/
 129 +
 130 +static void __iomem *membase;
 131 +static struct i2c_adapter *adapter;
 132 +
 133 +static void rt_i2c_w32(u32 val, unsigned reg)
 134 +{
 135 +       iowrite32(val, membase + reg);
 136 +}
 137 +
 138 +static u32 rt_i2c_r32(unsigned reg)
 139 +{
 140 +       return ioread32(membase + reg);
 141 +}
 142 +
 143 +static void mt7621_i2c_reset(struct i2c_adapter *a)
 144 +{
 145 +       device_reset(a->dev.parent);
 146 +}
 147 +static void mt7621_i2c_enable(struct i2c_msg *msg)
 148 +{
 149 +       rt_i2c_w32(msg->addr,REG_DEVADDR_REG);
 150 +       rt_i2c_w32(0,REG_ADDR_REG);
 151 +}
 152 +
 153 +static void i2c_master_init(struct i2c_adapter *a)
 154 +{
 155 +       mt7621_i2c_reset(a);
 156 +       rt_i2c_w32(I2C_CFG_DEFAULT,REG_CONFIG_REG);
 157 +       rt_i2c_w32(SM0_CFG_DEFUALT,REG_SM0CTL0);
 158 +       rt_i2c_w32(1,REG_SM0_IS_AUTOMODE);//auto mode
 159 +}
 160 +
 161 +
 162 +static inline int rt_i2c_wait_rx_done(void)
 163 +{
 164 +       int i=0;
 165 +       while((!(rt_i2c_r32(REG_STATUS_REG) & I2C_DATARDY)) && (i<i2c_busy_loop))
 166 +               i++;
 167 +       if(i>=i2c_busy_loop){
 168 +               pr_err("err,wait for idle timeout");
 169 +               return -ETIMEDOUT;
 170 +       }
 171 +       return 0;
 172 +}
 173 +
 174 +static inline int rt_i2c_wait_idle(void)
 175 +{
 176 +       int i=0;
 177 +       while((rt_i2c_r32(REG_STATUS_REG) & I2C_BUSY) && (i<i2c_busy_loop))
 178 +               i++;
 179 +       if(i>=i2c_busy_loop){
 180 +               pr_err("err,wait for idle timeout");
 181 +               return -ETIMEDOUT;
 182 +       }
 183 +       return 0;
 184 +}
 185 +
 186 +static inline int rt_i2c_wait_tx_done(void)
 187 +{
 188 +       int i=0;
 189 +       while((!(rt_i2c_r32(REG_STATUS_REG) & I2C_SDOEMPTY)) && (i<i2c_busy_loop))
 190 +               i++;
 191 +       if(i>=i2c_busy_loop){
 192 +               pr_err("err,wait for idle timeout");
 193 +               return -ETIMEDOUT;
 194 +       }
 195 +       return 0;
 196 +}
 197 +
 198 +static int rt_i2c_handle_msg(struct i2c_adapter *a, struct i2c_msg* msg)
 199 +{
 200 +       int i = 0, j = 0, pos = 0;
 201 +       int nblock = msg->len / READ_BLOCK;
 202 +       int rem = msg->len % READ_BLOCK;
 203 +
 204 +       if (msg->flags & I2C_M_TEN) {
 205 +               printk("10 bits addr not supported\n");
 206 +               return -EINVAL;
 207 +       }
 208 +
 209 +       if (msg->flags & I2C_M_RD) {
 210 +               for (i = 0; i < nblock; i++) {
 211 +                       if (rt_i2c_wait_idle())
 212 +                               goto err_timeout;
 213 +                       rt_i2c_w32(READ_BLOCK - 1, REG_BYTECNT_REG);
 214 +                       rt_i2c_w32(READ_CMD, REG_STARTXFR_REG);
 215 +                       for (j = 0; j < READ_BLOCK; j++) {
 216 +                               if (rt_i2c_wait_rx_done())
 217 +                                       goto err_timeout;
 218 +                               msg->buf[pos++] = rt_i2c_r32(REG_DATAIN_REG);
 219 +                       }
 220 +               }
 221 +
 222 +               if (rt_i2c_wait_idle())
 223 +                   goto err_timeout;
 224 +               rt_i2c_w32(rem - 1, REG_BYTECNT_REG);
 225 +               rt_i2c_w32(READ_CMD, REG_STARTXFR_REG);
 226 +
 227 +               for (i = 0; i < rem; i++) {
 228 +                       if (rt_i2c_wait_rx_done())
 229 +                               goto err_timeout;
 230 +                       msg->buf[pos++] = rt_i2c_r32(REG_DATAIN_REG);
 231 +               }
 232 +       } else {
 233 +               if (rt_i2c_wait_idle())
 234 +                       goto err_timeout;
 235 +               rt_i2c_w32(msg->len - 1, REG_BYTECNT_REG);
 236 +               for (i = 0; i < msg->len; i++) {
 237 +                       rt_i2c_w32(msg->buf[i], REG_DATAOUT_REG);
 238 +                       if(i == 0)
 239 +                               rt_i2c_w32(WRITE_CMD, REG_STARTXFR_REG);
 240 +
 241 +                       if (rt_i2c_wait_tx_done())
 242 +                               goto err_timeout;
 243 +               }
 244 +       }
 245 +
 246 +       return 0;
 247 +err_timeout:
 248 +       return -ETIMEDOUT;
 249 +}
 250 +
 251 +static int rt_i2c_master_xfer(struct i2c_adapter *a, struct i2c_msg *m, int n)
 252 +{
 253 +       int i = 0;
 254 +       int ret = 0;
 255 +       i2c_master_init(a);
 256 +       mt7621_i2c_enable(m);
 257 +
 258 +       for (i = 0; i != n && ret==0; i++) {
 259 +               ret = rt_i2c_handle_msg(a, &m[i]);
 260 +               if (ret)
 261 +                       return ret;
 262 +       }
 263 +       return i;
 264 +}
 265 +
 266 +static u32 rt_i2c_func(struct i2c_adapter *a)
 267 +{
 268 +       return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
 269 +}
 270 +
 271 +static const struct i2c_algorithm rt_i2c_algo = {
 272 +       .master_xfer    = rt_i2c_master_xfer,
 273 +       .functionality  = rt_i2c_func,
 274 +};
 275 +
 276 +static int rt_i2c_probe(struct platform_device *pdev)
 277 +{
 278 +       struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 279 +       int ret;
 280 +
 281 +       adapter = devm_kzalloc(&pdev->dev,sizeof(struct i2c_adapter), GFP_KERNEL);
 282 +       if (!adapter) {
 283 +               dev_err(&pdev->dev, "failed to allocate i2c_adapter\n");
 284 +               return -ENOMEM;
 285 +       }
 286 +       membase = devm_ioremap_resource(&pdev->dev, res);
 287 +       if (IS_ERR(membase))
 288 +               return PTR_ERR(membase);
 289 +
 290 +       strlcpy(adapter->name, dev_name(&pdev->dev), sizeof(adapter->name));
 291 +
 292 +       adapter->owner = THIS_MODULE;
 293 +       adapter->nr = pdev->id;
 294 +       adapter->timeout = HZ;
 295 +       adapter->algo = &rt_i2c_algo;
 296 +       adapter->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
 297 +       adapter->dev.parent = &pdev->dev;
 298 +       adapter->dev.of_node = pdev->dev.of_node;
 299 +
 300 +       platform_set_drvdata(pdev, adapter);
 301 +
 302 +       ret = i2c_add_numbered_adapter(adapter);
 303 +       if (ret)
 304 +               return ret;
 305 +
 306 +       dev_info(&pdev->dev,"loaded");
 307 +
 308 +       return 0;
 309 +}
 310 +
 311 +static int rt_i2c_remove(struct platform_device *pdev)
 312 +{
 313 +       platform_set_drvdata(pdev, NULL);
 314 +       return 0;
 315 +}
 316 +
 317 +static const struct of_device_id i2c_rt_dt_ids[] = {
 318 +       { .compatible = "ralink,i2c-mt7621", },
 319 +       { /* sentinel */ }
 320 +};
 321 +
 322 +MODULE_DEVICE_TABLE(of, i2c_rt_dt_ids);
 323 +
 324 +static struct platform_driver rt_i2c_driver = {
 325 +       .probe          = rt_i2c_probe,
 326 +       .remove         = rt_i2c_remove,
 327 +       .driver         = {
 328 +               .owner  = THIS_MODULE,
 329 +               .name   = "i2c-mt7621",
 330 +               .of_match_table = i2c_rt_dt_ids,
 331 +       },
 332 +};
 333 +
 334 +static int __init i2c_rt_init (void)
 335 +{
 336 +       return platform_driver_register(&rt_i2c_driver);
 337 +}
 338 +
 339 +static void __exit i2c_rt_exit (void)
 340 +{
 341 +       platform_driver_unregister(&rt_i2c_driver);
 342 +}
 343 +module_init (i2c_rt_init);
 344 +module_exit (i2c_rt_exit);
 345 +
 346 +MODULE_AUTHOR("Steven Liu <steven_liu@mediatek.com>");
 347 +MODULE_DESCRIPTION("MT7621 I2c host driver");
 348 +MODULE_LICENSE("GPL");
 349 +MODULE_ALIAS("platform:MT7621-I2C");
 350 --
 351 1.7.10.4
 352