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|
---
drivers/i2c/busses/Kconfig | 5 +
drivers/i2c/busses/Makefile | 1
drivers/i2c/busses/i2c-ep93xx.c | 194 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 200 insertions(+)
--- linux-2.6.32.orig/drivers/i2c/busses/Kconfig
+++ linux-2.6.32/drivers/i2c/busses/Kconfig
@@ -351,10 +351,15 @@ config I2C_DESIGNWARE
Synopsys DesignWare I2C adapter. Only master mode is supported.
This driver can also be built as a module. If so, the module
will be called i2c-designware.
+config I2C_EP93XX
+ tristate "EP93XX I2C"
+ depends on I2C && ARCH_EP93XX
+ select I2C_ALGOBIT
+
config I2C_GPIO
tristate "GPIO-based bitbanging I2C"
depends on GENERIC_GPIO
select I2C_ALGOBIT
help
--- linux-2.6.32.orig/drivers/i2c/busses/Makefile
+++ linux-2.6.32/drivers/i2c/busses/Makefile
@@ -72,9 +72,10 @@ obj-$(CONFIG_I2C_PCA_PLATFORM) += i2c-pc
obj-$(CONFIG_I2C_PMCMSP) += i2c-pmcmsp.o
obj-$(CONFIG_I2C_SIBYTE) += i2c-sibyte.o
obj-$(CONFIG_I2C_STUB) += i2c-stub.o
obj-$(CONFIG_SCx200_ACB) += scx200_acb.o
obj-$(CONFIG_SCx200_I2C) += scx200_i2c.o
+obj-$(CONFIG_I2C_EP93XX) += i2c-ep93xx.o
ifeq ($(CONFIG_I2C_DEBUG_BUS),y)
EXTRA_CFLAGS += -DDEBUG
endif
--- /dev/null
+++ linux-2.6.32/drivers/i2c/busses/i2c-ep93xx.c
@@ -0,0 +1,194 @@
+/* ------------------------------------------------------------------------ *
+ * i2c-ep933xx.c I2C bus glue for Cirrus EP93xx *
+ * ------------------------------------------------------------------------ *
+
+ Copyright (C) 2004 Michael Burian
+
+ Based on i2c-parport-light.c
+ Copyright (C) 2003-2004 Jean Delvare <khali@linux-fr.org>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ * ------------------------------------------------------------------------ */
+
+
+//#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/i2c-algo-bit.h>
+#include <asm/io.h>
+#include <mach/hardware.h>
+
+//1/(2*clockfrequency)
+#define EE_DELAY_USEC 50
+#define GPIOG_EECLK 1
+#define GPIOG_EEDAT 2
+
+/* ----- I2C algorithm call-back functions and structures ----------------- */
+
+// TODO: optimize
+static void ep93xx_setscl(void *data, int state)
+{
+ unsigned int uiPGDR, uiPGDDR;
+
+ uiPGDR = inl(GPIO_PGDR);
+ uiPGDDR = inl(GPIO_PGDDR);
+
+ /* Configure the clock line as output. */
+ uiPGDDR |= GPIOG_EECLK;
+ outl(uiPGDDR, GPIO_PGDDR);
+
+ /* Set clock line to state */
+ if(state)
+ uiPGDR |= GPIOG_EECLK;
+ else
+ uiPGDR &= ~GPIOG_EECLK;
+
+ outl(uiPGDR, GPIO_PGDR);
+}
+
+static void ep93xx_setsda(void *data, int state)
+{
+ unsigned int uiPGDR, uiPGDDR;
+
+ uiPGDR = inl(GPIO_PGDR);
+ uiPGDDR = inl(GPIO_PGDDR);
+
+ /* Configure the data line as output. */
+ uiPGDDR |= GPIOG_EEDAT;
+ outl(uiPGDDR, GPIO_PGDDR);
+
+ /* Set data line to state */
+ if(state)
+ uiPGDR |= GPIOG_EEDAT;
+ else
+ uiPGDR &= ~GPIOG_EEDAT;
+
+ outl(uiPGDR, GPIO_PGDR);
+}
+
+static int ep93xx_getscl(void *data)
+{
+ unsigned int uiPGDR, uiPGDDR;
+
+ uiPGDR = inl(GPIO_PGDR);
+ uiPGDDR = inl(GPIO_PGDDR);
+
+ /* Configure the clock line as input */
+ uiPGDDR &= ~GPIOG_EECLK;
+ outl(uiPGDDR, GPIO_PGDDR);
+
+ /* Return state of the clock line */
+ return (inl(GPIO_PGDR) & GPIOG_EECLK) ? 1 : 0;
+}
+
+static int ep93xx_getsda(void *data)
+{
+ unsigned int uiPGDR, uiPGDDR;
+ uiPGDR = inl(GPIO_PGDR);
+ uiPGDDR = inl(GPIO_PGDDR);
+
+ /* Configure the data line as input */
+ uiPGDDR &= ~GPIOG_EEDAT;
+ outl(uiPGDDR, GPIO_PGDDR);
+
+ /* Return state of the data line */
+ return (inl(GPIO_PGDR) & GPIOG_EEDAT) ? 1 : 0;
+}
+
+/* ------------------------------------------------------------------------
+ * Encapsulate the above functions in the correct operations structure.
+ * This is only done when more than one hardware adapter is supported.
+ */
+
+/* last line (us, ms, timeout)
+ * us dominates the bit rate: 10us means: 100Kbit/sec(25 means 40kbps)
+ * 10ms not known
+ * 100ms timeout
+ */
+static struct i2c_algo_bit_data ep93xx_data = {
+ .setsda = ep93xx_setsda,
+ .setscl = ep93xx_setscl,
+ .getsda = ep93xx_getsda,
+ .getscl = ep93xx_getscl,
+ .udelay = 10,
+ //.mdelay = 10,
+ .timeout = HZ,
+};
+
+/* ----- I2c structure ---------------------------------------------------- */
+static struct i2c_adapter ep93xx_adapter = {
+ .owner = THIS_MODULE,
+ .class = I2C_CLASS_HWMON,
+/* .id = I2C_HW_B_LP,*/
+ .algo_data = &ep93xx_data,
+ .name = "EP93XX I2C bit-bang interface",
+};
+
+/* ----- Module loading, unloading and information ------------------------ */
+
+static int __init i2c_ep93xx_init(void)
+{
+ unsigned long uiPGDR, uiPGDDR;
+
+ /* Read the current value of the GPIO data and data direction registers. */
+ uiPGDR = inl(GPIO_PGDR);
+ uiPGDDR = inl(GPIO_PGDDR);
+
+ /* If the GPIO pins have not been configured since reset, the data
+ * and clock lines will be set as inputs and with data value of 0.
+ * External pullup resisters are pulling them high.
+ * Set them both high before configuring them as outputs. */
+ uiPGDR |= (GPIOG_EEDAT | GPIOG_EECLK);
+ outl(uiPGDR, GPIO_PGDR);
+
+ /* Delay to meet the EE Interface timing specification. */
+ udelay(EE_DELAY_USEC);
+
+
+ /* Configure the EE data and clock lines as outputs. */
+ uiPGDDR |= (GPIOG_EEDAT | GPIOG_EECLK);
+ outl(uiPGDDR, GPIO_PGDDR);
+
+ /* Delay to meet the EE Interface timing specification. */
+ udelay(EE_DELAY_USEC);
+
+ /* Reset hardware to a sane state (SCL and SDA high) */
+ ep93xx_setsda(NULL, 1);
+ ep93xx_setscl(NULL, 1);
+
+ if (i2c_bit_add_bus(&ep93xx_adapter) > 0) {
+ printk(KERN_ERR "i2c-ep93xx: Unable to register with I2C\n");
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+static void __exit i2c_ep93xx_exit(void)
+{
+ //i2c_bit_del_bus(&ep93xx_adapter);
+ i2c_del_adapter(&ep93xx_adapter);
+}
+
+MODULE_AUTHOR("Michael Burian");
+MODULE_DESCRIPTION("I2C bus glue for Cirrus EP93xx processors");
+MODULE_LICENSE("GPL");
+
+module_init(i2c_ep93xx_init);
+module_exit(i2c_ep93xx_exit);
|
