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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-09 16:08:04 +0900
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-09 16:08:04 +0900
commitde390bba797aa9a554bc1769b6a8771605854d79 (patch)
treece95610d4a70ec0a7307a30cfd1a66fdf0c901ab /arch/mips/mti-sead3/sead3-i2c-drv.c
parent50e0d10232db05c6776afcf6098459bff47e8b15 (diff)
parent382fc33b4a04e2dde89b4c69a6880e0c7d9761e2 (diff)
Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS update from Ralf Baechle: "This is the MIPS update for 3.7. A fair chunk of them are platform updates to the Cavium Octeon SOC (which involves machine generated header files of considerable size), Atheros ATH79xx, RMI aka Netlogic aka Broadcom XLP, Broadcom BCM63xx platforms. Support for the commercial MIPS simulator MIPSsim has been removed as MIPS Technologies is shifting away from this product and Qemu is offering various more powerful platforms. The generic MIPS code can now also probe for no-execute / write-only TLB features implemented without the full SmartMIPS extension as permitted by the latest MIPS processor architecture. Lots of small changes to generic code." * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (78 commits) MIPS: ath79: Fix CPU/DDR frequency calculation for SRIF PLLs MIPS: ath79: use correct fractional dividers for {CPU,DDR}_PLL on AR934x MIPS: BCM63XX: Properly handle mac address octet overflow MIPS: Kconfig: Avoid build errors by hiding USE_OF from the user. MIPS: Replace `-' in defconfig filename wth `_' for consistency. MIPS: Wire kcmp syscall. MIPS: MIPSsim: Remove the MIPSsim platform. MIPS: NOTIFY_RESUME is not needed in TIF masks MIPS: Merge the identical "return from syscall" per-ABI code MIPS: Unobfuscate _TIF..._MASK MIPS: Prevent hitting do_notify_resume() with !user_mode(regs). MIPS: Replace 'kernel_uses_smartmips_rixi' with 'cpu_has_rixi'. MIPS: Add base architecture support for RI and XI. MIPS: Optimise TLB handlers for MIPS32/64 R2 cores. MIPS: uasm: Add INS and EXT instructions. MIPS: Avoid pipeline stalls on some MIPS32R2 cores. MIPS: Make VPE count to be one-based. MIPS: Add new end of interrupt functionality for GIC. MIPS: Add EIC support for GIC. MIPS: Code clean-ups for the GIC. ...
Diffstat (limited to 'arch/mips/mti-sead3/sead3-i2c-drv.c')
-rw-r--r--arch/mips/mti-sead3/sead3-i2c-drv.c405
1 files changed, 405 insertions, 0 deletions
diff --git a/arch/mips/mti-sead3/sead3-i2c-drv.c b/arch/mips/mti-sead3/sead3-i2c-drv.c
new file mode 100644
index 000000000000..0375ee66bca3
--- /dev/null
+++ b/arch/mips/mti-sead3/sead3-i2c-drv.c
@@ -0,0 +1,405 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved.
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/platform_device.h>
+
+#define PIC32_I2CxCON 0x0000
+#define PIC32_I2CCON_ON (1<<15)
+#define PIC32_I2CCON_ACKDT (1<<5)
+#define PIC32_I2CCON_ACKEN (1<<4)
+#define PIC32_I2CCON_RCEN (1<<3)
+#define PIC32_I2CCON_PEN (1<<2)
+#define PIC32_I2CCON_RSEN (1<<1)
+#define PIC32_I2CCON_SEN (1<<0)
+#define PIC32_I2CxCONCLR 0x0004
+#define PIC32_I2CxCONSET 0x0008
+#define PIC32_I2CxSTAT 0x0010
+#define PIC32_I2CxSTATCLR 0x0014
+#define PIC32_I2CSTAT_ACKSTAT (1<<15)
+#define PIC32_I2CSTAT_TRSTAT (1<<14)
+#define PIC32_I2CSTAT_BCL (1<<10)
+#define PIC32_I2CSTAT_IWCOL (1<<7)
+#define PIC32_I2CSTAT_I2COV (1<<6)
+#define PIC32_I2CxBRG 0x0040
+#define PIC32_I2CxTRN 0x0050
+#define PIC32_I2CxRCV 0x0060
+
+static DEFINE_SPINLOCK(pic32_bus_lock);
+
+static void __iomem *bus_xfer = (void __iomem *)0xbf000600;
+static void __iomem *bus_status = (void __iomem *)0xbf000060;
+
+#define DELAY() udelay(100)
+
+static inline unsigned int ioready(void)
+{
+ return readl(bus_status) & 1;
+}
+
+static inline void wait_ioready(void)
+{
+ do { } while (!ioready());
+}
+
+static inline void wait_ioclear(void)
+{
+ do { } while (ioready());
+}
+
+static inline void check_ioclear(void)
+{
+ if (ioready()) {
+ do {
+ (void) readl(bus_xfer);
+ DELAY();
+ } while (ioready());
+ }
+}
+
+static u32 pic32_bus_readl(u32 reg)
+{
+ unsigned long flags;
+ u32 status, val;
+
+ spin_lock_irqsave(&pic32_bus_lock, flags);
+
+ check_ioclear();
+ writel((0x01 << 24) | (reg & 0x00ffffff), bus_xfer);
+ DELAY();
+ wait_ioready();
+ status = readl(bus_xfer);
+ DELAY();
+ val = readl(bus_xfer);
+ wait_ioclear();
+
+ spin_unlock_irqrestore(&pic32_bus_lock, flags);
+
+ return val;
+}
+
+static void pic32_bus_writel(u32 val, u32 reg)
+{
+ unsigned long flags;
+ u32 status;
+
+ spin_lock_irqsave(&pic32_bus_lock, flags);
+
+ check_ioclear();
+ writel((0x10 << 24) | (reg & 0x00ffffff), bus_xfer);
+ DELAY();
+ writel(val, bus_xfer);
+ DELAY();
+ wait_ioready();
+ status = readl(bus_xfer);
+ wait_ioclear();
+
+ spin_unlock_irqrestore(&pic32_bus_lock, flags);
+}
+
+struct pic32_i2c_platform_data {
+ u32 base;
+ struct i2c_adapter adap;
+ u32 xfer_timeout;
+ u32 ack_timeout;
+ u32 ctl_timeout;
+};
+
+static inline void pic32_i2c_start(struct pic32_i2c_platform_data *adap)
+{
+ pic32_bus_writel(PIC32_I2CCON_SEN, adap->base + PIC32_I2CxCONSET);
+}
+
+static inline void pic32_i2c_stop(struct pic32_i2c_platform_data *adap)
+{
+ pic32_bus_writel(PIC32_I2CCON_PEN, adap->base + PIC32_I2CxCONSET);
+}
+
+static inline void pic32_i2c_ack(struct pic32_i2c_platform_data *adap)
+{
+ pic32_bus_writel(PIC32_I2CCON_ACKDT, adap->base + PIC32_I2CxCONCLR);
+ pic32_bus_writel(PIC32_I2CCON_ACKEN, adap->base + PIC32_I2CxCONSET);
+}
+
+static inline void pic32_i2c_nack(struct pic32_i2c_platform_data *adap)
+{
+ pic32_bus_writel(PIC32_I2CCON_ACKDT, adap->base + PIC32_I2CxCONSET);
+ pic32_bus_writel(PIC32_I2CCON_ACKEN, adap->base + PIC32_I2CxCONSET);
+}
+
+static inline int pic32_i2c_idle(struct pic32_i2c_platform_data *adap)
+{
+ int i;
+
+ for (i = 0; i < adap->ctl_timeout; i++) {
+ if (((pic32_bus_readl(adap->base + PIC32_I2CxCON) &
+ (PIC32_I2CCON_ACKEN | PIC32_I2CCON_RCEN |
+ PIC32_I2CCON_PEN | PIC32_I2CCON_RSEN |
+ PIC32_I2CCON_SEN)) == 0) &&
+ ((pic32_bus_readl(adap->base + PIC32_I2CxSTAT) &
+ (PIC32_I2CSTAT_TRSTAT)) == 0))
+ return 0;
+ udelay(1);
+ }
+ return -ETIMEDOUT;
+}
+
+static inline u32 pic32_i2c_master_write(struct pic32_i2c_platform_data *adap,
+ u32 byte)
+{
+ pic32_bus_writel(byte, adap->base + PIC32_I2CxTRN);
+ return pic32_bus_readl(adap->base + PIC32_I2CxSTAT) &
+ PIC32_I2CSTAT_IWCOL;
+}
+
+static inline u32 pic32_i2c_master_read(struct pic32_i2c_platform_data *adap)
+{
+ pic32_bus_writel(PIC32_I2CCON_RCEN, adap->base + PIC32_I2CxCONSET);
+ while (pic32_bus_readl(adap->base + PIC32_I2CxCON) & PIC32_I2CCON_RCEN)
+ ;
+ pic32_bus_writel(PIC32_I2CSTAT_I2COV, adap->base + PIC32_I2CxSTATCLR);
+ return pic32_bus_readl(adap->base + PIC32_I2CxRCV);
+}
+
+static int pic32_i2c_address(struct pic32_i2c_platform_data *adap,
+ unsigned int addr, int rd)
+{
+ pic32_i2c_idle(adap);
+ pic32_i2c_start(adap);
+ pic32_i2c_idle(adap);
+
+ addr <<= 1;
+ if (rd)
+ addr |= 1;
+
+ if (pic32_i2c_master_write(adap, addr))
+ return -EIO;
+ pic32_i2c_idle(adap);
+ if (pic32_bus_readl(adap->base + PIC32_I2CxSTAT) &
+ PIC32_I2CSTAT_ACKSTAT)
+ return -EIO;
+ return 0;
+}
+
+static int sead3_i2c_read(struct pic32_i2c_platform_data *adap,
+ unsigned char *buf, unsigned int len)
+{
+ u32 data;
+ int i;
+
+ i = 0;
+ while (i < len) {
+ data = pic32_i2c_master_read(adap);
+ buf[i++] = data;
+ if (i < len)
+ pic32_i2c_ack(adap);
+ else
+ pic32_i2c_nack(adap);
+ }
+
+ pic32_i2c_stop(adap);
+ pic32_i2c_idle(adap);
+ return 0;
+}
+
+static int sead3_i2c_write(struct pic32_i2c_platform_data *adap,
+ unsigned char *buf, unsigned int len)
+{
+ int i;
+ u32 data;
+
+ i = 0;
+ while (i < len) {
+ data = buf[i];
+ if (pic32_i2c_master_write(adap, data))
+ return -EIO;
+ pic32_i2c_idle(adap);
+ if (pic32_bus_readl(adap->base + PIC32_I2CxSTAT) &
+ PIC32_I2CSTAT_ACKSTAT)
+ return -EIO;
+ i++;
+ }
+
+ pic32_i2c_stop(adap);
+ pic32_i2c_idle(adap);
+ return 0;
+}
+
+static int sead3_pic32_platform_xfer(struct i2c_adapter *i2c_adap,
+ struct i2c_msg *msgs, int num)
+{
+ struct pic32_i2c_platform_data *adap = i2c_adap->algo_data;
+ struct i2c_msg *p;
+ int i, err = 0;
+
+ for (i = 0; i < num; i++) {
+#define __BUFSIZE 80
+ int ii;
+ static char buf[__BUFSIZE];
+ char *b = buf;
+
+ p = &msgs[i];
+ b += sprintf(buf, " [%d bytes]", p->len);
+ if ((p->flags & I2C_M_RD) == 0) {
+ for (ii = 0; ii < p->len; ii++) {
+ if (b < &buf[__BUFSIZE-4]) {
+ b += sprintf(b, " %02x", p->buf[ii]);
+ } else {
+ strcat(b, "...");
+ break;
+ }
+ }
+ }
+ }
+
+ for (i = 0; !err && i < num; i++) {
+ p = &msgs[i];
+ err = pic32_i2c_address(adap, p->addr, p->flags & I2C_M_RD);
+ if (err || !p->len)
+ continue;
+ if (p->flags & I2C_M_RD)
+ err = sead3_i2c_read(adap, p->buf, p->len);
+ else
+ err = sead3_i2c_write(adap, p->buf, p->len);
+ }
+
+ /* Return the number of messages processed, or the error code. */
+ if (err == 0)
+ err = num;
+
+ return err;
+}
+
+static u32 sead3_pic32_platform_func(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm sead3_platform_algo = {
+ .master_xfer = sead3_pic32_platform_xfer,
+ .functionality = sead3_pic32_platform_func,
+};
+
+static void sead3_i2c_platform_setup(struct pic32_i2c_platform_data *priv)
+{
+ pic32_bus_writel(500, priv->base + PIC32_I2CxBRG);
+ pic32_bus_writel(PIC32_I2CCON_ON, priv->base + PIC32_I2CxCONCLR);
+ pic32_bus_writel(PIC32_I2CCON_ON, priv->base + PIC32_I2CxCONSET);
+ pic32_bus_writel(PIC32_I2CSTAT_BCL | PIC32_I2CSTAT_IWCOL,
+ priv->base + PIC32_I2CxSTATCLR);
+}
+
+static int __devinit sead3_i2c_platform_probe(struct platform_device *pdev)
+{
+ struct pic32_i2c_platform_data *priv;
+ struct resource *r;
+ int ret;
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!r) {
+ ret = -ENODEV;
+ goto out;
+ }
+
+ priv = kzalloc(sizeof(struct pic32_i2c_platform_data), GFP_KERNEL);
+ if (!priv) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ priv->base = r->start;
+ if (!priv->base) {
+ ret = -EBUSY;
+ goto out_mem;
+ }
+
+ priv->xfer_timeout = 200;
+ priv->ack_timeout = 200;
+ priv->ctl_timeout = 200;
+
+ priv->adap.nr = pdev->id;
+ priv->adap.algo = &sead3_platform_algo;
+ priv->adap.algo_data = priv;
+ priv->adap.dev.parent = &pdev->dev;
+ strlcpy(priv->adap.name, "SEAD3 PIC32", sizeof(priv->adap.name));
+
+ sead3_i2c_platform_setup(priv);
+
+ ret = i2c_add_numbered_adapter(&priv->adap);
+ if (ret == 0) {
+ platform_set_drvdata(pdev, priv);
+ return 0;
+ }
+
+out_mem:
+ kfree(priv);
+out:
+ return ret;
+}
+
+static int __devexit sead3_i2c_platform_remove(struct platform_device *pdev)
+{
+ struct pic32_i2c_platform_data *priv = platform_get_drvdata(pdev);
+
+ platform_set_drvdata(pdev, NULL);
+ i2c_del_adapter(&priv->adap);
+ kfree(priv);
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int sead3_i2c_platform_suspend(struct platform_device *pdev,
+ pm_message_t state)
+{
+ dev_dbg(&pdev->dev, "i2c_platform_disable\n");
+ return 0;
+}
+
+static int sead3_i2c_platform_resume(struct platform_device *pdev)
+{
+ struct pic32_i2c_platform_data *priv = platform_get_drvdata(pdev);
+
+ dev_dbg(&pdev->dev, "sead3_i2c_platform_setup\n");
+ sead3_i2c_platform_setup(priv);
+
+ return 0;
+}
+#else
+#define sead3_i2c_platform_suspend NULL
+#define sead3_i2c_platform_resume NULL
+#endif
+
+static struct platform_driver sead3_i2c_platform_driver = {
+ .driver = {
+ .name = "sead3-i2c",
+ .owner = THIS_MODULE,
+ },
+ .probe = sead3_i2c_platform_probe,
+ .remove = __devexit_p(sead3_i2c_platform_remove),
+ .suspend = sead3_i2c_platform_suspend,
+ .resume = sead3_i2c_platform_resume,
+};
+
+static int __init sead3_i2c_platform_init(void)
+{
+ return platform_driver_register(&sead3_i2c_platform_driver);
+}
+module_init(sead3_i2c_platform_init);
+
+static void __exit sead3_i2c_platform_exit(void)
+{
+ platform_driver_unregister(&sead3_i2c_platform_driver);
+}
+module_exit(sead3_i2c_platform_exit);
+
+MODULE_AUTHOR("Chris Dearman, MIPS Technologies INC.");
+MODULE_DESCRIPTION("SEAD3 PIC32 I2C driver");
+MODULE_LICENSE("GPL");