summaryrefslogtreecommitdiffstats
path: root/arch/mips/mti-sead3/sead3-pic32-i2c-drv.c
diff options
context:
space:
mode:
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-pic32-i2c-drv.c
parent50e0d10232db05c6776afcf6098459bff47e8b15 (diff)
parent382fc33b4a04e2dde89b4c69a6880e0c7d9761e2 (diff)
downloadtalos-obmc-linux-de390bba797aa9a554bc1769b6a8771605854d79.tar.gz
talos-obmc-linux-de390bba797aa9a554bc1769b6a8771605854d79.zip
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-pic32-i2c-drv.c')
-rw-r--r--arch/mips/mti-sead3/sead3-pic32-i2c-drv.c435
1 files changed, 435 insertions, 0 deletions
diff --git a/arch/mips/mti-sead3/sead3-pic32-i2c-drv.c b/arch/mips/mti-sead3/sead3-pic32-i2c-drv.c
new file mode 100644
index 000000000000..46509b0a620d
--- /dev/null
+++ b/arch/mips/mti-sead3/sead3-pic32-i2c-drv.c
@@ -0,0 +1,435 @@
+/*
+ * 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/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/platform_device.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/i2c.h>
+#include <linux/slab.h>
+
+#define PIC32_I2CxCON 0x0000
+#define PIC32_I2CxCONCLR 0x0004
+#define PIC32_I2CxCONSET 0x0008
+#define PIC32_I2CxCONINV 0x000C
+#define I2CCON_ON (1<<15)
+#define I2CCON_FRZ (1<<14)
+#define I2CCON_SIDL (1<<13)
+#define I2CCON_SCLREL (1<<12)
+#define I2CCON_STRICT (1<<11)
+#define I2CCON_A10M (1<<10)
+#define I2CCON_DISSLW (1<<9)
+#define I2CCON_SMEN (1<<8)
+#define I2CCON_GCEN (1<<7)
+#define I2CCON_STREN (1<<6)
+#define I2CCON_ACKDT (1<<5)
+#define I2CCON_ACKEN (1<<4)
+#define I2CCON_RCEN (1<<3)
+#define I2CCON_PEN (1<<2)
+#define I2CCON_RSEN (1<<1)
+#define I2CCON_SEN (1<<0)
+
+#define PIC32_I2CxSTAT 0x0010
+#define PIC32_I2CxSTATCLR 0x0014
+#define PIC32_I2CxSTATSET 0x0018
+#define PIC32_I2CxSTATINV 0x001C
+#define I2CSTAT_ACKSTAT (1<<15)
+#define I2CSTAT_TRSTAT (1<<14)
+#define I2CSTAT_BCL (1<<10)
+#define I2CSTAT_GCSTAT (1<<9)
+#define I2CSTAT_ADD10 (1<<8)
+#define I2CSTAT_IWCOL (1<<7)
+#define I2CSTAT_I2COV (1<<6)
+#define I2CSTAT_DA (1<<5)
+#define I2CSTAT_P (1<<4)
+#define I2CSTAT_S (1<<3)
+#define I2CSTAT_RW (1<<2)
+#define I2CSTAT_RBF (1<<1)
+#define I2CSTAT_TBF (1<<0)
+
+#define PIC32_I2CxADD 0x0020
+#define PIC32_I2CxADDCLR 0x0024
+#define PIC32_I2CxADDSET 0x0028
+#define PIC32_I2CxADDINV 0x002C
+#define PIC32_I2CxMSK 0x0030
+#define PIC32_I2CxMSKCLR 0x0034
+#define PIC32_I2CxMSKSET 0x0038
+#define PIC32_I2CxMSKINV 0x003C
+#define PIC32_I2CxBRG 0x0040
+#define PIC32_I2CxBRGCLR 0x0044
+#define PIC32_I2CxBRGSET 0x0048
+#define PIC32_I2CxBRGINV 0x004C
+#define PIC32_I2CxTRN 0x0050
+#define PIC32_I2CxTRNCLR 0x0054
+#define PIC32_I2CxTRNSET 0x0058
+#define PIC32_I2CxTRNINV 0x005C
+#define PIC32_I2CxRCV 0x0060
+
+struct i2c_platform_data {
+ u32 base;
+ struct i2c_adapter adap;
+ u32 xfer_timeout;
+ u32 ack_timeout;
+ u32 ctl_timeout;
+};
+
+extern u32 pic32_bus_readl(u32 reg);
+extern void pic32_bus_writel(u32 val, u32 reg);
+
+static inline void
+StartI2C(struct i2c_platform_data *adap)
+{
+ pr_debug("StartI2C\n");
+ pic32_bus_writel(I2CCON_SEN, adap->base + PIC32_I2CxCONSET);
+}
+
+static inline void
+StopI2C(struct i2c_platform_data *adap)
+{
+ pr_debug("StopI2C\n");
+ pic32_bus_writel(I2CCON_PEN, adap->base + PIC32_I2CxCONSET);
+}
+
+static inline void
+AckI2C(struct i2c_platform_data *adap)
+{
+ pr_debug("AckI2C\n");
+ pic32_bus_writel(I2CCON_ACKDT, adap->base + PIC32_I2CxCONCLR);
+ pic32_bus_writel(I2CCON_ACKEN, adap->base + PIC32_I2CxCONSET);
+}
+
+static inline void
+NotAckI2C(struct i2c_platform_data *adap)
+{
+ pr_debug("NakI2C\n");
+ pic32_bus_writel(I2CCON_ACKDT, adap->base + PIC32_I2CxCONSET);
+ pic32_bus_writel(I2CCON_ACKEN, adap->base + PIC32_I2CxCONSET);
+}
+
+static inline int
+IdleI2C(struct i2c_platform_data *adap)
+{
+ int i;
+
+ pr_debug("IdleI2C\n");
+ for (i = 0; i < adap->ctl_timeout; i++) {
+ if (((pic32_bus_readl(adap->base + PIC32_I2CxCON) &
+ (I2CCON_ACKEN | I2CCON_RCEN | I2CCON_PEN | I2CCON_RSEN |
+ I2CCON_SEN)) == 0) &&
+ ((pic32_bus_readl(adap->base + PIC32_I2CxSTAT) &
+ (I2CSTAT_TRSTAT)) == 0))
+ return 0;
+ udelay(1);
+ }
+ return -ETIMEDOUT;
+}
+
+static inline u32
+MasterWriteI2C(struct i2c_platform_data *adap, u32 byte)
+{
+ pr_debug("MasterWriteI2C\n");
+
+ pic32_bus_writel(byte, adap->base + PIC32_I2CxTRN);
+
+ return pic32_bus_readl(adap->base + PIC32_I2CxSTAT) & I2CSTAT_IWCOL;
+}
+
+static inline u32
+MasterReadI2C(struct i2c_platform_data *adap)
+{
+ pr_debug("MasterReadI2C\n");
+
+ pic32_bus_writel(I2CCON_RCEN, adap->base + PIC32_I2CxCONSET);
+
+ while (pic32_bus_readl(adap->base + PIC32_I2CxCON) & I2CCON_RCEN)
+ ;
+
+ pic32_bus_writel(I2CSTAT_I2COV, adap->base + PIC32_I2CxSTATCLR);
+
+ return pic32_bus_readl(adap->base + PIC32_I2CxRCV);
+}
+
+static int
+do_address(struct i2c_platform_data *adap, unsigned int addr, int rd)
+{
+ pr_debug("doaddress\n");
+
+ IdleI2C(adap);
+ StartI2C(adap);
+ IdleI2C(adap);
+
+ addr <<= 1;
+ if (rd)
+ addr |= 1;
+
+ if (MasterWriteI2C(adap, addr))
+ return -EIO;
+ IdleI2C(adap);
+ if (pic32_bus_readl(adap->base + PIC32_I2CxSTAT) & I2CSTAT_ACKSTAT)
+ return -EIO;
+ return 0;
+}
+
+static int
+i2c_read(struct i2c_platform_data *adap, unsigned char *buf,
+ unsigned int len)
+{
+ int i;
+ u32 data;
+
+ pr_debug("i2c_read\n");
+
+ i = 0;
+ while (i < len) {
+ data = MasterReadI2C(adap);
+ buf[i++] = data;
+ if (i < len)
+ AckI2C(adap);
+ else
+ NotAckI2C(adap);
+ }
+
+ StopI2C(adap);
+ IdleI2C(adap);
+ return 0;
+}
+
+static int
+i2c_write(struct i2c_platform_data *adap, unsigned char *buf,
+ unsigned int len)
+{
+ int i;
+ u32 data;
+
+ pr_debug("i2c_write\n");
+
+ i = 0;
+ while (i < len) {
+ data = buf[i];
+ if (MasterWriteI2C(adap, data))
+ return -EIO;
+ IdleI2C(adap);
+ if (pic32_bus_readl(adap->base + PIC32_I2CxSTAT) &
+ I2CSTAT_ACKSTAT)
+ return -EIO;
+ i++;
+ }
+
+ StopI2C(adap);
+ IdleI2C(adap);
+ return 0;
+}
+
+static int
+platform_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
+{
+ struct i2c_platform_data *adap = i2c_adap->algo_data;
+ struct i2c_msg *p;
+ int i, err = 0;
+
+ pr_debug("platform_xfer\n");
+ 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;
+ }
+ }
+ }
+ pr_debug("xfer%d: DevAddr: %04x Op:%s Data:%s\n", i, p->addr,
+ (p->flags & I2C_M_RD) ? "Rd" : "Wr", buf);
+ }
+
+
+ for (i = 0; !err && i < num; i++) {
+ p = &msgs[i];
+ err = do_address(adap, p->addr, p->flags & I2C_M_RD);
+ if (err || !p->len)
+ continue;
+ if (p->flags & I2C_M_RD)
+ err = i2c_read(adap, p->buf, p->len);
+ else
+ err = 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
+platform_func(struct i2c_adapter *adap)
+{
+ pr_debug("platform_algo\n");
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm platform_algo = {
+ .master_xfer = platform_xfer,
+ .functionality = platform_func,
+};
+
+static void i2c_platform_setup(struct i2c_platform_data *priv)
+{
+ pr_debug("i2c_platform_setup\n");
+
+ pic32_bus_writel(500, priv->base + PIC32_I2CxBRG);
+ pic32_bus_writel(I2CCON_ON, priv->base + PIC32_I2CxCONCLR);
+ pic32_bus_writel(I2CCON_ON, priv->base + PIC32_I2CxCONSET);
+ pic32_bus_writel((I2CSTAT_BCL | I2CSTAT_IWCOL),
+ (priv->base + PIC32_I2CxSTATCLR));
+}
+
+static void i2c_platform_disable(struct i2c_platform_data *priv)
+{
+ pr_debug("i2c_platform_disable\n");
+}
+
+static int __devinit
+i2c_platform_probe(struct platform_device *pdev)
+{
+ struct i2c_platform_data *priv;
+ struct resource *r;
+ int ret;
+
+ pr_debug("i2c_platform_probe\n");
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!r) {
+ ret = -ENODEV;
+ goto out;
+ }
+
+ priv = kzalloc(sizeof(struct i2c_platform_data), GFP_KERNEL);
+ if (!priv) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ /* FIXME: need to allocate resource in PIC32 space */
+#if 0
+ priv->base = bus_request_region(r->start, resource_size(r),
+ pdev->name);
+#else
+ priv->base = r->start;
+#endif
+ 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 = &platform_algo;
+ priv->adap.algo_data = priv;
+ priv->adap.dev.parent = &pdev->dev;
+ strlcpy(priv->adap.name, "PIC32 I2C", sizeof(priv->adap.name));
+
+ i2c_platform_setup(priv);
+
+ ret = i2c_add_numbered_adapter(&priv->adap);
+ if (ret == 0) {
+ platform_set_drvdata(pdev, priv);
+ return 0;
+ }
+
+ i2c_platform_disable(priv);
+
+out_mem:
+ kfree(priv);
+out:
+ return ret;
+}
+
+static int __devexit
+i2c_platform_remove(struct platform_device *pdev)
+{
+ struct i2c_platform_data *priv = platform_get_drvdata(pdev);
+
+ pr_debug("i2c_platform_remove\n");
+ platform_set_drvdata(pdev, NULL);
+ i2c_del_adapter(&priv->adap);
+ i2c_platform_disable(priv);
+ kfree(priv);
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int
+i2c_platform_suspend(struct platform_device *pdev, pm_message_t state)
+{
+ struct i2c_platform_data *priv = platform_get_drvdata(pdev);
+
+ dev_dbg(&pdev->dev, "i2c_platform_disable\n");
+ i2c_platform_disable(priv);
+
+ return 0;
+}
+
+static int
+i2c_platform_resume(struct platform_device *pdev)
+{
+ struct i2c_platform_data *priv = platform_get_drvdata(pdev);
+
+ dev_dbg(&pdev->dev, "i2c_platform_setup\n");
+ i2c_platform_setup(priv);
+
+ return 0;
+}
+#else
+#define i2c_platform_suspend NULL
+#define i2c_platform_resume NULL
+#endif
+
+static struct platform_driver i2c_platform_driver = {
+ .driver = {
+ .name = "i2c_pic32",
+ .owner = THIS_MODULE,
+ },
+ .probe = i2c_platform_probe,
+ .remove = __devexit_p(i2c_platform_remove),
+ .suspend = i2c_platform_suspend,
+ .resume = i2c_platform_resume,
+};
+
+static int __init
+i2c_platform_init(void)
+{
+ pr_debug("i2c_platform_init\n");
+ return platform_driver_register(&i2c_platform_driver);
+}
+
+static void __exit
+i2c_platform_exit(void)
+{
+ pr_debug("i2c_platform_exit\n");
+ platform_driver_unregister(&i2c_platform_driver);
+}
+
+MODULE_AUTHOR("Chris Dearman, MIPS Technologies INC.");
+MODULE_DESCRIPTION("PIC32 I2C driver");
+MODULE_LICENSE("GPL");
+
+module_init(i2c_platform_init);
+module_exit(i2c_platform_exit);
OpenPOWER on IntegriCloud