target/linux/ep93xx/patches-2.6.30/003-ep93xx-i2c.patch

   1 Index: linux-2.6.30.9/drivers/i2c/busses/Kconfig
   2 ===================================================================
   3 --- linux-2.6.30.9.orig/drivers/i2c/busses/Kconfig      2009-11-24 21:00:21.000000000 +0100
   4 +++ linux-2.6.30.9/drivers/i2c/busses/Kconfig   2009-11-24 21:00:23.000000000 +0100
   5 @@ -326,6 +326,10 @@
   6           devices such as DaVinci NIC.
   7           For details please see http://www.ti.com/davinci
   8
   9 +config I2C_EP93XX
  10 +       tristate "EP93XX I2C"
  11 +       depends on I2C && ARCH_EP93XX
  12 +
  13  config I2C_GPIO
  14         tristate "GPIO-based bitbanging I2C"
  15         depends on GENERIC_GPIO
  16 Index: linux-2.6.30.9/drivers/i2c/busses/Makefile
  17 ===================================================================
  18 --- linux-2.6.30.9.orig/drivers/i2c/busses/Makefile     2009-11-24 21:00:21.000000000 +0100
  19 +++ linux-2.6.30.9/drivers/i2c/busses/Makefile  2009-11-24 21:00:23.000000000 +0100
  20 @@ -30,6 +30,7 @@
  21  obj-$(CONFIG_I2C_BLACKFIN_TWI) += i2c-bfin-twi.o
  22  obj-$(CONFIG_I2C_CPM)          += i2c-cpm.o
  23  obj-$(CONFIG_I2C_DAVINCI)      += i2c-davinci.o
  24 +obj-$(CONFIG_I2C_EP93XX)       += i2c-ep93xx.o
  25  obj-$(CONFIG_I2C_GPIO)         += i2c-gpio.o
  26  obj-$(CONFIG_I2C_HIGHLANDER)   += i2c-highlander.o
  27  obj-$(CONFIG_I2C_IBM_IIC)      += i2c-ibm_iic.o
  28 Index: linux-2.6.30.9/drivers/i2c/busses/i2c-ep93xx.c
  29 ===================================================================
  30 --- /dev/null   1970-01-01 00:00:00.000000000 +0000
  31 +++ linux-2.6.30.9/drivers/i2c/busses/i2c-ep93xx.c      2009-11-24 21:00:38.000000000 +0100
  32 @@ -0,0 +1,193 @@
  33 +/* ------------------------------------------------------------------------ *
  34 + * i2c-ep933xx.c I2C bus glue for Cirrus EP93xx                             *
  35 + * ------------------------------------------------------------------------ *
  36 +
  37 +   Copyright (C) 2004 Michael Burian
  38 +
  39 +   Based on i2c-parport-light.c
  40 +   Copyright (C) 2003-2004 Jean Delvare <khali@linux-fr.org>
  41 +
  42 +   This program is free software; you can redistribute it and/or modify
  43 +   it under the terms of the GNU General Public License as published by
  44 +   the Free Software Foundation; either version 2 of the License, or
  45 +   (at your option) any later version.
  46 +
  47 +   This program is distributed in the hope that it will be useful,
  48 +   but WITHOUT ANY WARRANTY; without even the implied warranty of
  49 +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  50 +   GNU General Public License for more details.
  51 +
  52 +   You should have received a copy of the GNU General Public License
  53 +   along with this program; if not, write to the Free Software
  54 +   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  55 + * ------------------------------------------------------------------------ */
  56 +
  57 +
  58 +//#include <linux/config.h>
  59 +#include <linux/kernel.h>
  60 +#include <linux/module.h>
  61 +#include <linux/init.h>
  62 +#include <linux/ioport.h>
  63 +#include <linux/delay.h>
  64 +#include <linux/i2c.h>
  65 +#include <linux/i2c-algo-bit.h>
  66 +#include <asm/io.h>
  67 +#include <mach/hardware.h>
  68 +
  69 +//1/(2*clockfrequency)
  70 +#define EE_DELAY_USEC       50
  71 +#define GPIOG_EECLK 1
  72 +#define GPIOG_EEDAT 2
  73 +
  74 +/* ----- I2C algorithm call-back functions and structures ----------------- */
  75 +
  76 +// TODO: optimize
  77 +static void ep93xx_setscl(void *data, int state)
  78 +{
  79 +       unsigned int uiPGDR, uiPGDDR;
  80 +
  81 +       uiPGDR = inl(GPIO_PGDR);
  82 +       uiPGDDR = inl(GPIO_PGDDR);
  83 +
  84 +       /* Configure the clock line as output. */
  85 +       uiPGDDR |= GPIOG_EECLK;
  86 +       outl(uiPGDDR, GPIO_PGDDR);
  87 +
  88 +       /* Set clock line to state */
  89 +       if(state)
  90 +               uiPGDR |= GPIOG_EECLK;
  91 +       else
  92 +               uiPGDR &= ~GPIOG_EECLK;
  93 +
  94 +       outl(uiPGDR, GPIO_PGDR);
  95 +}
  96 +
  97 +static void ep93xx_setsda(void *data, int state)
  98 +{
  99 +       unsigned int uiPGDR, uiPGDDR;
 100 +
 101 +       uiPGDR = inl(GPIO_PGDR);
 102 +       uiPGDDR = inl(GPIO_PGDDR);
 103 +
 104 +       /* Configure the data line as output. */
 105 +       uiPGDDR |= GPIOG_EEDAT;
 106 +       outl(uiPGDDR, GPIO_PGDDR);
 107 +
 108 +       /* Set data line to state */
 109 +       if(state)
 110 +               uiPGDR |= GPIOG_EEDAT;
 111 +       else
 112 +               uiPGDR &= ~GPIOG_EEDAT;
 113 +
 114 +       outl(uiPGDR, GPIO_PGDR);
 115 +}
 116 +
 117 +static int ep93xx_getscl(void *data)
 118 +{
 119 +       unsigned int uiPGDR, uiPGDDR;
 120 +
 121 +       uiPGDR = inl(GPIO_PGDR);
 122 +       uiPGDDR = inl(GPIO_PGDDR);
 123 +
 124 +       /* Configure the clock line as input */
 125 +       uiPGDDR &= ~GPIOG_EECLK;
 126 +       outl(uiPGDDR, GPIO_PGDDR);
 127 +
 128 +       /* Return state of the clock line */
 129 +       return (inl(GPIO_PGDR) & GPIOG_EECLK) ? 1 : 0;
 130 +}
 131 +
 132 +static int ep93xx_getsda(void *data)
 133 +{
 134 +       unsigned int uiPGDR, uiPGDDR;
 135 +       uiPGDR = inl(GPIO_PGDR);
 136 +       uiPGDDR = inl(GPIO_PGDDR);
 137 +
 138 +       /* Configure the data line as input */
 139 +       uiPGDDR &= ~GPIOG_EEDAT;
 140 +       outl(uiPGDDR, GPIO_PGDDR);
 141 +
 142 +       /* Return state of the data line */
 143 +       return (inl(GPIO_PGDR) & GPIOG_EEDAT) ? 1 : 0;
 144 +}
 145 +
 146 +/* ------------------------------------------------------------------------
 147 + * Encapsulate the above functions in the correct operations structure.
 148 + * This is only done when more than one hardware adapter is supported.
 149 + */
 150 +
 151 +/* last line (us, ms, timeout)
 152 + * us dominates the bit rate: 10us  means: 100Kbit/sec(25 means 40kbps)
 153 + *                            10ms  not known
 154 + *                            100ms timeout
 155 + */
 156 +static struct i2c_algo_bit_data ep93xx_data = {
 157 +       .setsda         = ep93xx_setsda,
 158 +       .setscl         = ep93xx_setscl,
 159 +       .getsda         = ep93xx_getsda,
 160 +       .getscl         = ep93xx_getscl,
 161 +       .udelay         = 10,
 162 +       //.mdelay               = 10,
 163 +       .timeout        = HZ,
 164 +};
 165 +
 166 +/* ----- I2c structure ---------------------------------------------------- */
 167 +static struct i2c_adapter ep93xx_adapter = {
 168 +       .owner          = THIS_MODULE,
 169 +       .class          = I2C_CLASS_HWMON,
 170 +       .algo_data      = &ep93xx_data,
 171 +       .name           = "EP93XX I2C bit-bang interface",
 172 +};
 173 +
 174 +/* ----- Module loading, unloading and information ------------------------ */
 175 +
 176 +static int __init i2c_ep93xx_init(void)
 177 +{
 178 +       unsigned long uiPGDR, uiPGDDR;
 179 +
 180 +       /* Read the current value of the GPIO data and data direction registers. */
 181 +       uiPGDR = inl(GPIO_PGDR);
 182 +       uiPGDDR = inl(GPIO_PGDDR);
 183 +
 184 +       /* If the GPIO pins have not been configured since reset, the data
 185 +        * and clock lines will be set as inputs and with data value of 0.
 186 +        * External pullup resisters are pulling them high.
 187 +        * Set them both high before configuring them as outputs. */
 188 +       uiPGDR |= (GPIOG_EEDAT | GPIOG_EECLK);
 189 +       outl(uiPGDR, GPIO_PGDR);
 190 +
 191 +       /* Delay to meet the EE Interface timing specification. */
 192 +       udelay(EE_DELAY_USEC);
 193 +
 194 +
 195 +       /* Configure the EE data and clock lines as outputs. */
 196 +       uiPGDDR |= (GPIOG_EEDAT | GPIOG_EECLK);
 197 +       outl(uiPGDDR, GPIO_PGDDR);
 198 +
 199 +       /* Delay to meet the EE Interface timing specification. */
 200 +       udelay(EE_DELAY_USEC);
 201 +
 202 +       /* Reset hardware to a sane state (SCL and SDA high) */
 203 +       ep93xx_setsda(NULL, 1);
 204 +       ep93xx_setscl(NULL, 1);
 205 +
 206 +       if (i2c_bit_add_bus(&ep93xx_adapter) > 0) {
 207 +               printk(KERN_ERR "i2c-ep93xx: Unable to register with I2C\n");
 208 +               return -ENODEV;
 209 +       }
 210 +
 211 +       return 0;
 212 +}
 213 +
 214 +static void __exit i2c_ep93xx_exit(void)
 215 +{
 216 +       //i2c_bit_del_bus(&ep93xx_adapter);
 217 +       i2c_del_adapter(&ep93xx_adapter);
 218 +}
 219 +
 220 +MODULE_AUTHOR("Michael Burian");
 221 +MODULE_DESCRIPTION("I2C bus glue for Cirrus EP93xx processors");
 222 +MODULE_LICENSE("GPL");
 223 +
 224 +module_init(i2c_ep93xx_init);
 225 +module_exit(i2c_ep93xx_exit);