unicore32 machine related files: add i2c bus drivers for pkunity-v3 soc
GuanXuetao [Sat, 26 Feb 2011 13:29:29 +0000 (21:29 +0800)]
change from original version -- by advice of Jean Delvare
1. remove global variable i2c_reg, replaced by local variables
2. replace ENXIO with ENODEV when no platform resources
3. add adapter->nr assignment before i2c_add_numbered_adapter() call
4. add judgement for i2c_del_adapter() return value
5. release adapter when driver removed
6. add __devexit for puv3_i2c_remove() function
7. modify several names to more appropriated ones

Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Acked-by: Arnd Bergmann <arnd@arndb.de>

MAINTAINERS
arch/unicore32/configs/debug_defconfig
drivers/i2c/busses/Kconfig
drivers/i2c/busses/Makefile
drivers/i2c/busses/i2c-puv3.c [new file with mode: 0644]

index e8b15bf..fa842ba 100644 (file)
@@ -4901,6 +4901,7 @@ W:        http://mprc.pku.edu.cn/~guanxuetao/linux
 S:     Maintained
 T:     git git://git.kernel.org/pub/scm/linux/kernel/git/epip/linux-2.6-unicore32.git
 F:     drivers/input/serio/i8042-unicore32io.h
+F:     drivers/i2c/busses/i2c-puv3.c
 
 PMC SIERRA MaxRAID DRIVER
 M:     Anil Ravindranath <anil_ravindranath@pmc-sierra.com>
index 3647f68..bf42abd 100644 (file)
@@ -114,6 +114,10 @@ CONFIG_INPUT_EVDEV=m
 #      Keyboards
 CONFIG_KEYBOARD_GPIO=m
 
+#      I2C support
+CONFIG_I2C=y
+CONFIG_I2C_PUV3=y
+
 #      Hardware Monitoring support
 #CONFIG_SENSORS_LM75=m
 #      Generic Thermal sysfs driver
index 113505a..cbfcf6f 100644 (file)
@@ -523,6 +523,17 @@ config I2C_PNX
          This driver can also be built as a module.  If so, the module
          will be called i2c-pnx.
 
+config I2C_PUV3
+       tristate "PKUnity v3 I2C bus support"
+       depends on UNICORE32 && ARCH_PUV3
+       select I2C_ALGOBIT
+       help
+         This driver supports the I2C IP inside the PKUnity-v3 SoC.
+         This I2C bus controller is under AMBA/AXI bus.
+
+         This driver can also be built as a module.  If so, the module
+         will be called i2c-puv3.
+
 config I2C_PXA
        tristate "Intel PXA2XX I2C adapter"
        depends on ARCH_PXA || ARCH_MMP
index 9d2d0ec..a83966a 100644 (file)
@@ -51,6 +51,7 @@ obj-$(CONFIG_I2C_PASEMI)      += i2c-pasemi.o
 obj-$(CONFIG_I2C_PCA_PLATFORM) += i2c-pca-platform.o
 obj-$(CONFIG_I2C_PMCMSP)       += i2c-pmcmsp.o
 obj-$(CONFIG_I2C_PNX)          += i2c-pnx.o
+obj-$(CONFIG_I2C_PUV3)         += i2c-puv3.o
 obj-$(CONFIG_I2C_PXA)          += i2c-pxa.o
 obj-$(CONFIG_I2C_S3C2410)      += i2c-s3c2410.o
 obj-$(CONFIG_I2C_S6000)                += i2c-s6000.o
diff --git a/drivers/i2c/busses/i2c-puv3.c b/drivers/i2c/busses/i2c-puv3.c
new file mode 100644 (file)
index 0000000..fac6739
--- /dev/null
@@ -0,0 +1,306 @@
+/*
+ * I2C driver for PKUnity-v3 SoC
+ * Code specific to PKUnity SoC and UniCore ISA
+ *
+ *     Maintained by GUAN Xue-tao <gxt@mprc.pku.edu.cn>
+ *     Copyright (C) 2001-2010 Guan Xuetao
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <mach/hardware.h>
+
+/*
+ * Poll the i2c status register until the specified bit is set.
+ * Returns 0 if timed out (100 msec).
+ */
+static short poll_status(unsigned long bit)
+{
+       int loop_cntr = 1000;
+
+       if (bit & I2C_STATUS_TFNF) {
+               do {
+                       udelay(10);
+               } while (!(readl(I2C_STATUS) & bit) && (--loop_cntr > 0));
+       } else {
+               /* RXRDY handler */
+               do {
+                       if (readl(I2C_TAR) == I2C_TAR_EEPROM)
+                               msleep(20);
+                       else
+                               udelay(10);
+               } while (!(readl(I2C_RXFLR) & 0xf) && (--loop_cntr > 0));
+       }
+
+       return (loop_cntr > 0);
+}
+
+static int xfer_read(struct i2c_adapter *adap, unsigned char *buf, int length)
+{
+       int i2c_reg = *buf;
+
+       /* Read data */
+       while (length--) {
+               if (!poll_status(I2C_STATUS_TFNF)) {
+                       dev_dbg(&adap->dev, "Tx FIFO Not Full timeout\n");
+                       return -ETIMEDOUT;
+               }
+
+               /* send addr */
+               writel(i2c_reg | I2C_DATACMD_WRITE, I2C_DATACMD);
+
+               /* get ready to next write */
+               i2c_reg++;
+
+               /* send read CMD */
+               writel(I2C_DATACMD_READ, I2C_DATACMD);
+
+               /* wait until the Rx FIFO have available */
+               if (!poll_status(I2C_STATUS_RFNE)) {
+                       dev_dbg(&adap->dev, "RXRDY timeout\n");
+                       return -ETIMEDOUT;
+               }
+
+               /* read the data to buf */
+               *buf = (readl(I2C_DATACMD) & I2C_DATACMD_DAT_MASK);
+               buf++;
+       }
+
+       return 0;
+}
+
+static int xfer_write(struct i2c_adapter *adap, unsigned char *buf, int length)
+{
+       int i2c_reg = *buf;
+
+       /* Do nothing but storing the reg_num to a static variable */
+       if (i2c_reg == -1) {
+               printk(KERN_WARNING "Error i2c reg\n");
+               return -ETIMEDOUT;
+       }
+
+       if (length == 1)
+               return 0;
+
+       buf++;
+       length--;
+       while (length--) {
+               /* send addr */
+               writel(i2c_reg | I2C_DATACMD_WRITE, I2C_DATACMD);
+
+               /* send write CMD */
+               writel(*buf | I2C_DATACMD_WRITE, I2C_DATACMD);
+
+               /* wait until the Rx FIFO have available */
+               msleep(20);
+
+               /* read the data to buf */
+               i2c_reg++;
+               buf++;
+       }
+
+       return 0;
+}
+
+/*
+ * Generic i2c master transfer entrypoint.
+ *
+ */
+static int puv3_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *pmsg,
+               int num)
+{
+       int i, ret;
+       unsigned char swap;
+
+       /* Disable i2c */
+       writel(I2C_ENABLE_DISABLE, I2C_ENABLE);
+
+       /* Set the work mode and speed*/
+       writel(I2C_CON_MASTER | I2C_CON_SPEED_STD | I2C_CON_SLAVEDISABLE, I2C_CON);
+
+       writel(pmsg->addr, I2C_TAR);
+
+       /* Enable i2c */
+       writel(I2C_ENABLE_ENABLE, I2C_ENABLE);
+
+       dev_dbg(&adap->dev, "puv3_i2c_xfer: processing %d messages:\n", num);
+
+       for (i = 0; i < num; i++) {
+               dev_dbg(&adap->dev, " #%d: %sing %d byte%s %s 0x%02x\n", i,
+                       pmsg->flags & I2C_M_RD ? "read" : "writ",
+                       pmsg->len, pmsg->len > 1 ? "s" : "",
+                       pmsg->flags & I2C_M_RD ? "from" : "to", pmsg->addr);
+
+               if (pmsg->len && pmsg->buf) {   /* sanity check */
+                       if (pmsg->flags & I2C_M_RD)
+                               ret = xfer_read(adap, pmsg->buf, pmsg->len);
+                       else
+                               ret = xfer_write(adap, pmsg->buf, pmsg->len);
+
+                       if (ret)
+                               return ret;
+
+               }
+               dev_dbg(&adap->dev, "transfer complete\n");
+               pmsg++;         /* next message */
+       }
+
+       /* XXX: fixup be16_to_cpu in bq27x00_battery.c */
+       if (pmsg->addr == I2C_TAR_PWIC) {
+               swap = pmsg->buf[0];
+               pmsg->buf[0] = pmsg->buf[1];
+               pmsg->buf[1] = swap;
+       }
+
+       return i;
+}
+
+/*
+ * Return list of supported functionality.
+ */
+static u32 puv3_i2c_func(struct i2c_adapter *adapter)
+{
+       return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static struct i2c_algorithm puv3_i2c_algorithm = {
+       .master_xfer    = puv3_i2c_xfer,
+       .functionality  = puv3_i2c_func,
+};
+
+/*
+ * Main initialization routine.
+ */
+static int __devinit puv3_i2c_probe(struct platform_device *pdev)
+{
+       struct i2c_adapter *adapter;
+       struct resource *mem;
+       int rc;
+
+       mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       if (!mem)
+               return -ENODEV;
+
+       if (!request_mem_region(mem->start, resource_size(mem), "puv3_i2c"))
+               return -EBUSY;
+
+       adapter = kzalloc(sizeof(struct i2c_adapter), GFP_KERNEL);
+       if (adapter == NULL) {
+               dev_err(&pdev->dev, "can't allocate inteface!\n");
+               rc = -ENOMEM;
+               goto fail_nomem;
+       }
+       snprintf(adapter->name, sizeof(adapter->name), "PUV3-I2C at 0x%08x",
+                       mem->start);
+       adapter->algo = &puv3_i2c_algorithm;
+       adapter->class = I2C_CLASS_HWMON;
+       adapter->dev.parent = &pdev->dev;
+
+       platform_set_drvdata(pdev, adapter);
+
+       adapter->nr = pdev->id;
+       rc = i2c_add_numbered_adapter(adapter);
+       if (rc) {
+               dev_err(&pdev->dev, "Adapter '%s' registration failed\n",
+                               adapter->name);
+               goto fail_add_adapter;
+       }
+
+       dev_info(&pdev->dev, "PKUnity v3 i2c bus adapter.\n");
+       return 0;
+
+fail_add_adapter:
+       platform_set_drvdata(pdev, NULL);
+       kfree(adapter);
+fail_nomem:
+       release_mem_region(mem->start, resource_size(mem));
+
+       return rc;
+}
+
+static int __devexit puv3_i2c_remove(struct platform_device *pdev)
+{
+       struct i2c_adapter *adapter = platform_get_drvdata(pdev);
+       struct resource *mem;
+       int rc;
+
+       rc = i2c_del_adapter(adapter);
+       if (rc) {
+               dev_err(&pdev->dev, "Adapter '%s' delete fail\n",
+                               adapter->name);
+               return rc;
+       }
+
+       put_device(&pdev->dev);
+       platform_set_drvdata(pdev, NULL);
+
+       mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       release_mem_region(mem->start, resource_size(mem));
+
+       return rc;
+}
+
+#ifdef CONFIG_PM
+static int puv3_i2c_suspend(struct platform_device *dev, pm_message_t state)
+{
+       int poll_count;
+       /* Disable the IIC */
+       writel(I2C_ENABLE_DISABLE, I2C_ENABLE);
+       for (poll_count = 0; poll_count < 50; poll_count++) {
+               if (readl(I2C_ENSTATUS) & I2C_ENSTATUS_ENABLE)
+                       udelay(25);
+       }
+
+       return 0;
+}
+
+static int puv3_i2c_resume(struct platform_device *dev)
+{
+       return 0 ;
+}
+#else
+#define puv3_i2c_suspend NULL
+#define puv3_i2c_resume NULL
+#endif
+
+MODULE_ALIAS("platform:puv3_i2c");
+
+static struct platform_driver puv3_i2c_driver = {
+       .probe          = puv3_i2c_probe,
+       .remove         = __devexit_p(puv3_i2c_remove),
+       .suspend        = puv3_i2c_suspend,
+       .resume         = puv3_i2c_resume,
+       .driver         = {
+               .name   = "PKUnity-v3-I2C",
+               .owner  = THIS_MODULE,
+       }
+};
+
+static int __init puv3_i2c_init(void)
+{
+       return platform_driver_register(&puv3_i2c_driver);
+}
+
+static void __exit puv3_i2c_exit(void)
+{
+       platform_driver_unregister(&puv3_i2c_driver);
+}
+
+module_init(puv3_i2c_init);
+module_exit(puv3_i2c_exit);
+
+MODULE_DESCRIPTION("PKUnity v3 I2C driver");
+MODULE_LICENSE("GPL v2");