Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-12-14 07:02:23 +00:00
Code Issues Packages Projects Releases Wiki Activity
a49f0d1ea3
linux/drivers/i2c/busses/i2c-mpc.c
Linus Torvalds 12250d843e Merge branch 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux 
Pull i2c-embedded changes from Wolfram Sang:
 "The changes for i2c-embedded include:

   - massive rework of the omap driver
   - massive rework of the at91 driver.  In fact, the old driver gets
     removed; I am okay with this approach since the old driver was
     depending on BROKEN and its limitations made it practically
     unusable, so people used bitbanging instead.  But even if there are
     users, there is no platform_data or module parameter which would
     need to be converted.  It is just another driver doing I2C
     transfers, just way better.  Modifications of arch/arm/at91 related
     files have proper acks from the maintainer.
   - new driver for R-Car I2C
   - devicetree and generic_clock conversions and fixes
   - usual driver fixes and changes.

  The rework patches have come a long way and lots of people have been
  involved in creating/testing them.  Most patches have been in
  linux-next at least since 3.6-rc5.  A few have been added in the last
  week, I have to admit.

  An unexpected (but welcome :)) peak in private life is the cause for
  that.  The "late" patches shouldn't cause any merge conflicts and I
  will have a special eye on them during the stabilization phase.  This
  is an exception and I want to have the patches in place properly in
  time again for the next kernels."

* 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux: (44 commits)
  MXS: Implement DMA support into mxs-i2c
  i2c: add Renesas R-Car I2C driver
  i2c: s3c2410: use clk_prepare_enable and clk_disable_unprepare
  ARM: OMAP: convert I2C driver to PM QoS for MPU latency constraints
  i2c: nomadik: Add Device Tree support to the Nomadik I2C driver
  i2c: algo: pca: Fix chip reset function for PCA9665
  i2c: mpc: Wait for STOP to hit the bus
  i2c: davinci: preparation for switch to common clock framework
  omap-i2c: fix incorrect log message when using a device tree
  i2c: omap: sanitize exit path
  i2c: omap: switch over to autosuspend API
  i2c: omap: remove unnecessary pm_runtime_suspended check
  i2c: omap: switch to threaded IRQ support
  i2c: omap: remove redundant status read
  i2c: omap: get rid of the "complete" label
  i2c: omap: resize fifos before each message
  i2c: omap: simplify IRQ exit path
  i2c: omap: always return IRQ_HANDLED
  i2c: omap: simplify errata check
  i2c: omap: bus: add a receiver flag
  ...
2012-10-11 10:27:51 +09:00

805 lines
20 KiB
C
Raw Blame History

/*
* (C) Copyright 2003-2004
* Humboldt Solutions Ltd, adrian@humboldt.co.uk.
* This is a combined i2c adapter and algorithm driver for the
* MPC107/Tsi107 PowerPC northbridge and processors that include
* the same I2C unit (8240, 8245, 85xx).
*
* Release 0.8
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/of_platform.h>
#include <linux/of_i2c.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/fsl_devices.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <asm/mpc52xx.h>
#include <sysdev/fsl_soc.h>
#define DRV_NAME "mpc-i2c"
#define MPC_I2C_CLOCK_LEGACY 0
#define MPC_I2C_CLOCK_PRESERVE (~0U)
#define MPC_I2C_FDR 0x04
#define MPC_I2C_CR 0x08
#define MPC_I2C_SR 0x0c
#define MPC_I2C_DR 0x10
#define MPC_I2C_DFSRR 0x14
#define CCR_MEN 0x80
#define CCR_MIEN 0x40
#define CCR_MSTA 0x20
#define CCR_MTX 0x10
#define CCR_TXAK 0x08
#define CCR_RSTA 0x04
#define CSR_MCF 0x80
#define CSR_MAAS 0x40
#define CSR_MBB 0x20
#define CSR_MAL 0x10
#define CSR_SRW 0x04
#define CSR_MIF 0x02
#define CSR_RXAK 0x01
struct mpc_i2c {
struct device *dev;
void __iomem *base;
u32 interrupt;
wait_queue_head_t queue;
struct i2c_adapter adap;
int irq;
u32 real_clk;
#ifdef CONFIG_PM
u8 fdr, dfsrr;
#endif
};
struct mpc_i2c_divider {
u16 divider;
u16 fdr; /* including dfsrr */
};
struct mpc_i2c_data {
void (*setup)(struct device_node *node, struct mpc_i2c *i2c,
u32 clock, u32 prescaler);
u32 prescaler;
};
static inline void writeccr(struct mpc_i2c *i2c, u32 x)
{
writeb(x, i2c->base + MPC_I2C_CR);
}
static irqreturn_t mpc_i2c_isr(int irq, void *dev_id)
{
struct mpc_i2c *i2c = dev_id;
if (readb(i2c->base + MPC_I2C_SR) & CSR_MIF) {
/* Read again to allow register to stabilise */
i2c->interrupt = readb(i2c->base + MPC_I2C_SR);
writeb(0, i2c->base + MPC_I2C_SR);
wake_up(&i2c->queue);
}
return IRQ_HANDLED;
}
/* Sometimes 9th clock pulse isn't generated, and slave doesn't release
* the bus, because it wants to send ACK.
* Following sequence of enabling/disabling and sending start/stop generates
* the 9 pulses, so it's all OK.
*/
static void mpc_i2c_fixup(struct mpc_i2c *i2c)
{
int k;
u32 delay_val = 1000000 / i2c->real_clk + 1;
if (delay_val < 2)
delay_val = 2;
for (k = 9; k; k--) {
writeccr(i2c, 0);
writeccr(i2c, CCR_MSTA | CCR_MTX | CCR_MEN);
udelay(delay_val);
writeccr(i2c, CCR_MEN);
udelay(delay_val << 1);
}
}
static int i2c_wait(struct mpc_i2c *i2c, unsigned timeout, int writing)
{
unsigned long orig_jiffies = jiffies;
u32 x;
int result = 0;
if (!i2c->irq) {
while (!(readb(i2c->base + MPC_I2C_SR) & CSR_MIF)) {
schedule();
if (time_after(jiffies, orig_jiffies + timeout)) {
dev_dbg(i2c->dev, "timeout\n");
writeccr(i2c, 0);
result = -EIO;
break;
}
}
x = readb(i2c->base + MPC_I2C_SR);
writeb(0, i2c->base + MPC_I2C_SR);
} else {
/* Interrupt mode */
result = wait_event_timeout(i2c->queue,
(i2c->interrupt & CSR_MIF), timeout);
if (unlikely(!(i2c->interrupt & CSR_MIF))) {
dev_dbg(i2c->dev, "wait timeout\n");
writeccr(i2c, 0);
result = -ETIMEDOUT;
}
x = i2c->interrupt;
i2c->interrupt = 0;
}
if (result < 0)
return result;
if (!(x & CSR_MCF)) {
dev_dbg(i2c->dev, "unfinished\n");
return -EIO;
}
if (x & CSR_MAL) {
dev_dbg(i2c->dev, "MAL\n");
return -EIO;
}
if (writing && (x & CSR_RXAK)) {
dev_dbg(i2c->dev, "No RXAK\n");
/* generate stop */
writeccr(i2c, CCR_MEN);
return -EIO;
}
return 0;
}
#if defined(CONFIG_PPC_MPC52xx) || defined(CONFIG_PPC_MPC512x)
static const struct mpc_i2c_divider mpc_i2c_dividers_52xx[] __devinitconst = {
{20, 0x20}, {22, 0x21}, {24, 0x22}, {26, 0x23},
{28, 0x24}, {30, 0x01}, {32, 0x25}, {34, 0x02},
{36, 0x26}, {40, 0x27}, {44, 0x04}, {48, 0x28},
{52, 0x63}, {56, 0x29}, {60, 0x41}, {64, 0x2a},
{68, 0x07}, {72, 0x2b}, {80, 0x2c}, {88, 0x09},
{96, 0x2d}, {104, 0x0a}, {112, 0x2e}, {120, 0x81},
{128, 0x2f}, {136, 0x47}, {144, 0x0c}, {160, 0x30},
{176, 0x49}, {192, 0x31}, {208, 0x4a}, {224, 0x32},
{240, 0x0f}, {256, 0x33}, {272, 0x87}, {288, 0x10},
{320, 0x34}, {352, 0x89}, {384, 0x35}, {416, 0x8a},
{448, 0x36}, {480, 0x13}, {512, 0x37}, {576, 0x14},
{640, 0x38}, {768, 0x39}, {896, 0x3a}, {960, 0x17},
{1024, 0x3b}, {1152, 0x18}, {1280, 0x3c}, {1536, 0x3d},
{1792, 0x3e}, {1920, 0x1b}, {2048, 0x3f}, {2304, 0x1c},
{2560, 0x1d}, {3072, 0x1e}, {3584, 0x7e}, {3840, 0x1f},
{4096, 0x7f}, {4608, 0x5c}, {5120, 0x5d}, {6144, 0x5e},
{7168, 0xbe}, {7680, 0x5f}, {8192, 0xbf}, {9216, 0x9c},
{10240, 0x9d}, {12288, 0x9e}, {15360, 0x9f}
};
static int __devinit mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock,
int prescaler, u32 *real_clk)
{
const struct mpc_i2c_divider *div = NULL;
unsigned int pvr = mfspr(SPRN_PVR);
u32 divider;
int i;
if (clock == MPC_I2C_CLOCK_LEGACY) {
/* see below - default fdr = 0x3f -> div = 2048 */
*real_clk = mpc5xxx_get_bus_frequency(node) / 2048;
return -EINVAL;
}
/* Determine divider value */
divider = mpc5xxx_get_bus_frequency(node) / clock;
/*
* We want to choose an FDR/DFSR that generates an I2C bus speed that
* is equal to or lower than the requested speed.
*/
for (i = 0; i < ARRAY_SIZE(mpc_i2c_dividers_52xx); i++) {
div = &mpc_i2c_dividers_52xx[i];
/* Old MPC5200 rev A CPUs do not support the high bits */
if (div->fdr & 0xc0 && pvr == 0x80822011)
continue;
if (div->divider >= divider)
break;
}
*real_clk = mpc5xxx_get_bus_frequency(node) / div->divider;
return (int)div->fdr;
}
static void __devinit mpc_i2c_setup_52xx(struct device_node *node,
struct mpc_i2c *i2c,
u32 clock, u32 prescaler)
{
int ret, fdr;
if (clock == MPC_I2C_CLOCK_PRESERVE) {
dev_dbg(i2c->dev, "using fdr %d\n",
readb(i2c->base + MPC_I2C_FDR));
return;
}
ret = mpc_i2c_get_fdr_52xx(node, clock, prescaler, &i2c->real_clk);
fdr = (ret >= 0) ? ret : 0x3f; /* backward compatibility */
writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR);
if (ret >= 0)
dev_info(i2c->dev, "clock %u Hz (fdr=%d)\n", i2c->real_clk,
fdr);
}
#else /* !(CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x) */
static void __devinit mpc_i2c_setup_52xx(struct device_node *node,
struct mpc_i2c *i2c,
u32 clock, u32 prescaler)
{
}
#endif /* CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x */
#ifdef CONFIG_PPC_MPC512x
static void __devinit mpc_i2c_setup_512x(struct device_node *node,
struct mpc_i2c *i2c,
u32 clock, u32 prescaler)
{
struct device_node *node_ctrl;
void __iomem *ctrl;
const u32 *pval;
u32 idx;
/* Enable I2C interrupts for mpc5121 */
node_ctrl = of_find_compatible_node(NULL, NULL,
"fsl,mpc5121-i2c-ctrl");
if (node_ctrl) {
ctrl = of_iomap(node_ctrl, 0);
if (ctrl) {
/* Interrupt enable bits for i2c-0/1/2: bit 24/26/28 */
pval = of_get_property(node, "reg", NULL);
idx = (*pval & 0xff) / 0x20;
setbits32(ctrl, 1 << (24 + idx * 2));
iounmap(ctrl);
}
of_node_put(node_ctrl);
}
/* The clock setup for the 52xx works also fine for the 512x */
mpc_i2c_setup_52xx(node, i2c, clock, prescaler);
}
#else /* CONFIG_PPC_MPC512x */
static void __devinit mpc_i2c_setup_512x(struct device_node *node,
struct mpc_i2c *i2c,
u32 clock, u32 prescaler)
{
}
#endif /* CONFIG_PPC_MPC512x */
#ifdef CONFIG_FSL_SOC
static const struct mpc_i2c_divider mpc_i2c_dividers_8xxx[] __devinitconst = {
{160, 0x0120}, {192, 0x0121}, {224, 0x0122}, {256, 0x0123},
{288, 0x0100}, {320, 0x0101}, {352, 0x0601}, {384, 0x0102},
{416, 0x0602}, {448, 0x0126}, {480, 0x0103}, {512, 0x0127},
{544, 0x0b03}, {576, 0x0104}, {608, 0x1603}, {640, 0x0105},
{672, 0x2003}, {704, 0x0b05}, {736, 0x2b03}, {768, 0x0106},
{800, 0x3603}, {832, 0x0b06}, {896, 0x012a}, {960, 0x0107},
{1024, 0x012b}, {1088, 0x1607}, {1152, 0x0108}, {1216, 0x2b07},
{1280, 0x0109}, {1408, 0x1609}, {1536, 0x010a}, {1664, 0x160a},
{1792, 0x012e}, {1920, 0x010b}, {2048, 0x012f}, {2176, 0x2b0b},
{2304, 0x010c}, {2560, 0x010d}, {2816, 0x2b0d}, {3072, 0x010e},
{3328, 0x2b0e}, {3584, 0x0132}, {3840, 0x010f}, {4096, 0x0133},
{4608, 0x0110}, {5120, 0x0111}, {6144, 0x0112}, {7168, 0x0136},
{7680, 0x0113}, {8192, 0x0137}, {9216, 0x0114}, {10240, 0x0115},
{12288, 0x0116}, {14336, 0x013a}, {15360, 0x0117}, {16384, 0x013b},
{18432, 0x0118}, {20480, 0x0119}, {24576, 0x011a}, {28672, 0x013e},
{30720, 0x011b}, {32768, 0x013f}, {36864, 0x011c}, {40960, 0x011d},
{49152, 0x011e}, {61440, 0x011f}
};
static u32 __devinit mpc_i2c_get_sec_cfg_8xxx(void)
{
struct device_node *node = NULL;
u32 __iomem *reg;
u32 val = 0;
node = of_find_node_by_name(NULL, "global-utilities");
if (node) {
const u32 *prop = of_get_property(node, "reg", NULL);
if (prop) {
/*
* Map and check POR Device Status Register 2
* (PORDEVSR2) at 0xE0014
*/
reg = ioremap(get_immrbase() + *prop + 0x14, 0x4);
if (!reg)
printk(KERN_ERR
"Error: couldn't map PORDEVSR2\n");
else
val = in_be32(reg) & 0x00000080; /* sec-cfg */
iounmap(reg);
}
}
if (node)
of_node_put(node);
return val;
}
static int __devinit mpc_i2c_get_fdr_8xxx(struct device_node *node, u32 clock,
u32 prescaler, u32 *real_clk)
{
const struct mpc_i2c_divider *div = NULL;
u32 divider;
int i;
if (clock == MPC_I2C_CLOCK_LEGACY) {
/* see below - default fdr = 0x1031 -> div = 16 * 3072 */
*real_clk = fsl_get_sys_freq() / prescaler / (16 * 3072);
return -EINVAL;
}
/* Determine proper divider value */
if (of_device_is_compatible(node, "fsl,mpc8544-i2c"))
prescaler = mpc_i2c_get_sec_cfg_8xxx() ? 3 : 2;
if (!prescaler)
prescaler = 1;
divider = fsl_get_sys_freq() / clock / prescaler;
pr_debug("I2C: src_clock=%d clock=%d divider=%d\n",
fsl_get_sys_freq(), clock, divider);
/*
* We want to choose an FDR/DFSR that generates an I2C bus speed that
* is equal to or lower than the requested speed.
*/
for (i = 0; i < ARRAY_SIZE(mpc_i2c_dividers_8xxx); i++) {
div = &mpc_i2c_dividers_8xxx[i];
if (div->divider >= divider)
break;
}
*real_clk = fsl_get_sys_freq() / prescaler / div->divider;
return div ? (int)div->fdr : -EINVAL;
}
static void __devinit mpc_i2c_setup_8xxx(struct device_node *node,
struct mpc_i2c *i2c,
u32 clock, u32 prescaler)
{
int ret, fdr;
if (clock == MPC_I2C_CLOCK_PRESERVE) {
dev_dbg(i2c->dev, "using dfsrr %d, fdr %d\n",
readb(i2c->base + MPC_I2C_DFSRR),
readb(i2c->base + MPC_I2C_FDR));
return;
}
ret = mpc_i2c_get_fdr_8xxx(node, clock, prescaler, &i2c->real_clk);
fdr = (ret >= 0) ? ret : 0x1031; /* backward compatibility */
writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR);
writeb((fdr >> 8) & 0xff, i2c->base + MPC_I2C_DFSRR);
if (ret >= 0)
dev_info(i2c->dev, "clock %d Hz (dfsrr=%d fdr=%d)\n",
i2c->real_clk, fdr >> 8, fdr & 0xff);
}
#else /* !CONFIG_FSL_SOC */
static void __devinit mpc_i2c_setup_8xxx(struct device_node *node,
struct mpc_i2c *i2c,
u32 clock, u32 prescaler)
{
}
#endif /* CONFIG_FSL_SOC */
static void mpc_i2c_start(struct mpc_i2c *i2c)
{
/* Clear arbitration */
writeb(0, i2c->base + MPC_I2C_SR);
/* Start with MEN */
writeccr(i2c, CCR_MEN);
}
static void mpc_i2c_stop(struct mpc_i2c *i2c)
{
writeccr(i2c, CCR_MEN);
}
static int mpc_write(struct mpc_i2c *i2c, int target,
const u8 *data, int length, int restart)
{
int i, result;
unsigned timeout = i2c->adap.timeout;
u32 flags = restart ? CCR_RSTA : 0;
/* Start as master */
writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX | flags);
/* Write target byte */
writeb((target << 1), i2c->base + MPC_I2C_DR);
result = i2c_wait(i2c, timeout, 1);
if (result < 0)
return result;
for (i = 0; i < length; i++) {
/* Write data byte */
writeb(data[i], i2c->base + MPC_I2C_DR);
result = i2c_wait(i2c, timeout, 1);
if (result < 0)
return result;
}
return 0;
}
static int mpc_read(struct mpc_i2c *i2c, int target,
u8 *data, int length, int restart, bool recv_len)
{
unsigned timeout = i2c->adap.timeout;
int i, result;
u32 flags = restart ? CCR_RSTA : 0;
/* Switch to read - restart */
writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX | flags);
/* Write target address byte - this time with the read flag set */
writeb((target << 1) | 1, i2c->base + MPC_I2C_DR);
result = i2c_wait(i2c, timeout, 1);
if (result < 0)
return result;
if (length) {
if (length == 1 && !recv_len)
writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_TXAK);
else
writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA);
/* Dummy read */
readb(i2c->base + MPC_I2C_DR);
}
for (i = 0; i < length; i++) {
u8 byte;
result = i2c_wait(i2c, timeout, 0);
if (result < 0)
return result;
/*
* For block reads, we have to know the total length (1st byte)
* before we can determine if we are done.
*/
if (i || !recv_len) {
/* Generate txack on next to last byte */
if (i == length - 2)
writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA
| CCR_TXAK);
/* Do not generate stop on last byte */
if (i == length - 1)
writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA
| CCR_MTX);
}
byte = readb(i2c->base + MPC_I2C_DR);
/*
* Adjust length if first received byte is length.
* The length is 1 length byte plus actually data length
*/
if (i == 0 && recv_len) {
if (byte == 0 || byte > I2C_SMBUS_BLOCK_MAX)
return -EPROTO;
length += byte;
/*
* For block reads, generate txack here if data length
* is 1 byte (total length is 2 bytes).
*/
if (length == 2)
writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA
| CCR_TXAK);
}
data[i] = byte;
}
return length;
}
static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
{
struct i2c_msg *pmsg;
int i;
int ret = 0;
unsigned long orig_jiffies = jiffies;
struct mpc_i2c *i2c = i2c_get_adapdata(adap);
mpc_i2c_start(i2c);
/* Allow bus up to 1s to become not busy */
while (readb(i2c->base + MPC_I2C_SR) & CSR_MBB) {
if (signal_pending(current)) {
dev_dbg(i2c->dev, "Interrupted\n");
writeccr(i2c, 0);
return -EINTR;
}
if (time_after(jiffies, orig_jiffies + HZ)) {
u8 status = readb(i2c->base + MPC_I2C_SR);
dev_dbg(i2c->dev, "timeout\n");
if ((status & (CSR_MCF | CSR_MBB | CSR_RXAK)) != 0) {
writeb(status & ~CSR_MAL,
i2c->base + MPC_I2C_SR);
mpc_i2c_fixup(i2c);
}
return -EIO;
}
schedule();
}
for (i = 0; ret >= 0 && i < num; i++) {
pmsg = &msgs[i];
dev_dbg(i2c->dev,
"Doing %s %d bytes to 0x%02x - %d of %d messages\n",
pmsg->flags & I2C_M_RD ? "read" : "write",
pmsg->len, pmsg->addr, i + 1, num);
if (pmsg->flags & I2C_M_RD) {
bool recv_len = pmsg->flags & I2C_M_RECV_LEN;
ret = mpc_read(i2c, pmsg->addr, pmsg->buf, pmsg->len, i,
recv_len);
if (recv_len && ret > 0)
pmsg->len = ret;
} else {
ret =
mpc_write(i2c, pmsg->addr, pmsg->buf, pmsg->len, i);
}
}
mpc_i2c_stop(i2c); /* Initiate STOP */
orig_jiffies = jiffies;
/* Wait until STOP is seen, allow up to 1 s */
while (readb(i2c->base + MPC_I2C_SR) & CSR_MBB) {
if (time_after(jiffies, orig_jiffies + HZ)) {
u8 status = readb(i2c->base + MPC_I2C_SR);
dev_dbg(i2c->dev, "timeout\n");
if ((status & (CSR_MCF | CSR_MBB | CSR_RXAK)) != 0) {
writeb(status & ~CSR_MAL,
i2c->base + MPC_I2C_SR);
mpc_i2c_fixup(i2c);
}
return -EIO;
}
cond_resched();
}
return (ret < 0) ? ret : num;
}
static u32 mpc_functionality(struct i2c_adapter *adap)
{
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL
| I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
}
static const struct i2c_algorithm mpc_algo = {
.master_xfer = mpc_xfer,
.functionality = mpc_functionality,
};
static struct i2c_adapter mpc_ops = {
.owner = THIS_MODULE,
.name = "MPC adapter",
.algo = &mpc_algo,
.timeout = HZ,
};
static const struct of_device_id mpc_i2c_of_match[];
static int __devinit fsl_i2c_probe(struct platform_device *op)
{
const struct of_device_id *match;
struct mpc_i2c *i2c;
const u32 *prop;
u32 clock = MPC_I2C_CLOCK_LEGACY;
int result = 0;
int plen;
match = of_match_device(mpc_i2c_of_match, &op->dev);
if (!match)
return -EINVAL;
i2c = kzalloc(sizeof(*i2c), GFP_KERNEL);
if (!i2c)
return -ENOMEM;
i2c->dev = &op->dev; /* for debug and error output */
init_waitqueue_head(&i2c->queue);
i2c->base = of_iomap(op->dev.of_node, 0);
if (!i2c->base) {
dev_err(i2c->dev, "failed to map controller\n");
result = -ENOMEM;
goto fail_map;
}
i2c->irq = irq_of_parse_and_map(op->dev.of_node, 0);
if (i2c->irq) { /* no i2c->irq implies polling */
result = request_irq(i2c->irq, mpc_i2c_isr,
IRQF_SHARED, "i2c-mpc", i2c);
if (result < 0) {
dev_err(i2c->dev, "failed to attach interrupt\n");
goto fail_request;
}
}
if (of_get_property(op->dev.of_node, "fsl,preserve-clocking", NULL)) {
clock = MPC_I2C_CLOCK_PRESERVE;
} else {
prop = of_get_property(op->dev.of_node, "clock-frequency",
&plen);
if (prop && plen == sizeof(u32))
clock = *prop;
}
if (match->data) {
const struct mpc_i2c_data *data = match->data;
data->setup(op->dev.of_node, i2c, clock, data->prescaler);
} else {
/* Backwards compatibility */
if (of_get_property(op->dev.of_node, "dfsrr", NULL))
mpc_i2c_setup_8xxx(op->dev.of_node, i2c, clock, 0);
}
prop = of_get_property(op->dev.of_node, "fsl,timeout", &plen);
if (prop && plen == sizeof(u32)) {
mpc_ops.timeout = *prop * HZ / 1000000;
if (mpc_ops.timeout < 5)
mpc_ops.timeout = 5;
}
dev_info(i2c->dev, "timeout %u us\n", mpc_ops.timeout * 1000000 / HZ);
dev_set_drvdata(&op->dev, i2c);
i2c->adap = mpc_ops;
i2c_set_adapdata(&i2c->adap, i2c);
i2c->adap.dev.parent = &op->dev;
i2c->adap.dev.of_node = of_node_get(op->dev.of_node);
result = i2c_add_adapter(&i2c->adap);
if (result < 0) {
dev_err(i2c->dev, "failed to add adapter\n");
goto fail_add;
}
of_i2c_register_devices(&i2c->adap);
return result;
fail_add:
dev_set_drvdata(&op->dev, NULL);
free_irq(i2c->irq, i2c);
fail_request:
irq_dispose_mapping(i2c->irq);
iounmap(i2c->base);
fail_map:
kfree(i2c);
return result;
};
static int __devexit fsl_i2c_remove(struct platform_device *op)
{
struct mpc_i2c *i2c = dev_get_drvdata(&op->dev);
i2c_del_adapter(&i2c->adap);
dev_set_drvdata(&op->dev, NULL);
if (i2c->irq)
free_irq(i2c->irq, i2c);
irq_dispose_mapping(i2c->irq);
iounmap(i2c->base);
kfree(i2c);
return 0;
};
#ifdef CONFIG_PM
static int mpc_i2c_suspend(struct device *dev)
{
struct mpc_i2c *i2c = dev_get_drvdata(dev);
i2c->fdr = readb(i2c->base + MPC_I2C_FDR);
i2c->dfsrr = readb(i2c->base + MPC_I2C_DFSRR);
return 0;
}
static int mpc_i2c_resume(struct device *dev)
{
struct mpc_i2c *i2c = dev_get_drvdata(dev);
writeb(i2c->fdr, i2c->base + MPC_I2C_FDR);
writeb(i2c->dfsrr, i2c->base + MPC_I2C_DFSRR);
return 0;
}
SIMPLE_DEV_PM_OPS(mpc_i2c_pm_ops, mpc_i2c_suspend, mpc_i2c_resume);
#endif
static const struct mpc_i2c_data mpc_i2c_data_512x __devinitdata = {
.setup = mpc_i2c_setup_512x,
};
static const struct mpc_i2c_data mpc_i2c_data_52xx __devinitdata = {
.setup = mpc_i2c_setup_52xx,
};
static const struct mpc_i2c_data mpc_i2c_data_8313 __devinitdata = {
.setup = mpc_i2c_setup_8xxx,
};
static const struct mpc_i2c_data mpc_i2c_data_8543 __devinitdata = {
.setup = mpc_i2c_setup_8xxx,
.prescaler = 2,
};
static const struct mpc_i2c_data mpc_i2c_data_8544 __devinitdata = {
.setup = mpc_i2c_setup_8xxx,
.prescaler = 3,
};
static const struct of_device_id mpc_i2c_of_match[] = {
{.compatible = "mpc5200-i2c", .data = &mpc_i2c_data_52xx, },
{.compatible = "fsl,mpc5200b-i2c", .data = &mpc_i2c_data_52xx, },
{.compatible = "fsl,mpc5200-i2c", .data = &mpc_i2c_data_52xx, },
{.compatible = "fsl,mpc5121-i2c", .data = &mpc_i2c_data_512x, },
{.compatible = "fsl,mpc8313-i2c", .data = &mpc_i2c_data_8313, },
{.compatible = "fsl,mpc8543-i2c", .data = &mpc_i2c_data_8543, },
{.compatible = "fsl,mpc8544-i2c", .data = &mpc_i2c_data_8544, },
/* Backward compatibility */
{.compatible = "fsl-i2c", },
{},
};
MODULE_DEVICE_TABLE(of, mpc_i2c_of_match);
/* Structure for a device driver */
static struct platform_driver mpc_i2c_driver = {
.probe = fsl_i2c_probe,
.remove = __devexit_p(fsl_i2c_remove),
.driver = {
.owner = THIS_MODULE,
.name = DRV_NAME,
.of_match_table = mpc_i2c_of_match,
#ifdef CONFIG_PM
.pm = &mpc_i2c_pm_ops,
#endif
},
};
module_platform_driver(mpc_i2c_driver);
MODULE_AUTHOR("Adrian Cox <adrian@humboldt.co.uk>");
MODULE_DESCRIPTION("I2C-Bus adapter for MPC107 bridge and "
"MPC824x/83xx/85xx/86xx/512x/52xx processors");
MODULE_LICENSE("GPL");
Reference in New Issue View Git Blame Copy Permalink