korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-12-02 08:34:20 +08:00
Code Issues Packages Projects Releases Wiki Activity
b29a1fc759
linux/drivers/i2c/busses/i2c-mpc.c
Arseny Solokha 38a99bd773 i2c: mpc: always determine I2C clock prescaler at runtime 
Remove the facility for setting the prescaler value at compile time
entirely. It was only used for two SoCs, duplicating the actual value
for one of them and setting sometimes bogus value for another. Make all
MPC8xxx SoCs obtain their actual I2C clock prescaler from a single place
in the code.

Changes from v2:
- left Device Tree compatibles in place

Signed-off-by: Arseny Solokha <asolokha@kb.kras.ru>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-15 19:19:55 +01:00

858 lines
22 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/signal.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/slab.h>
#include <linux/clk.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 <asm/mpc85xx.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_SLEEP
u8 fdr, dfsrr;
#endif
struct clk *clk_per;
};
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);
};
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;
}
return IRQ_NONE;
}
/* 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);
readb(i2c->base + MPC_I2C_DR);
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 cmd_err;
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 = -ETIMEDOUT;
break;
}
}
cmd_err = 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;
}
cmd_err = i2c->interrupt;
i2c->interrupt = 0;
}
if (result < 0)
return result;
if (!(cmd_err & CSR_MCF)) {
dev_dbg(i2c->dev, "unfinished\n");
return -EIO;
}
if (cmd_err & CSR_MAL) {
dev_dbg(i2c->dev, "MAL\n");
return -EAGAIN;
}
if (writing && (cmd_err & CSR_RXAK)) {
dev_dbg(i2c->dev, "No RXAK\n");
/* generate stop */
writeccr(i2c, CCR_MEN);
return -ENXIO;
}
return 0;
}
#if defined(CONFIG_PPC_MPC52xx) || defined(CONFIG_PPC_MPC512x)
static const struct mpc_i2c_divider mpc_i2c_dividers_52xx[] = {
{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 mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock,
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 mpc_i2c_setup_52xx(struct device_node *node,
struct mpc_i2c *i2c,
u32 clock)
{
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, &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 mpc_i2c_setup_52xx(struct device_node *node,
struct mpc_i2c *i2c,
u32 clock)
{
}
#endif /* CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x */
#ifdef CONFIG_PPC_MPC512x
static void mpc_i2c_setup_512x(struct device_node *node,
struct mpc_i2c *i2c,
u32 clock)
{
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);
}
#else /* CONFIG_PPC_MPC512x */
static void mpc_i2c_setup_512x(struct device_node *node,
struct mpc_i2c *i2c,
u32 clock)
{
}
#endif /* CONFIG_PPC_MPC512x */
#ifdef CONFIG_FSL_SOC
static const struct mpc_i2c_divider mpc_i2c_dividers_8xxx[] = {
{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 mpc_i2c_get_sec_cfg_8xxx(void)
{
struct device_node *node;
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. Note than while MPC8533
* and MPC8544 indicate SEC frequency ratio
* configuration as bit 26 in PORDEVSR2, other MPC8xxx
* parts may store it differently or may not have it
* at all.
*/
reg = ioremap(get_immrbase() + *prop + 0x14, 0x4);
if (!reg)
printk(KERN_ERR
"Error: couldn't map PORDEVSR2\n");
else
val = in_be32(reg) & 0x00000020; /* sec-cfg */
iounmap(reg);
}
}
of_node_put(node);
return val;
}
static u32 mpc_i2c_get_prescaler_8xxx(void)
{
/*
* According to the AN2919 all MPC824x have prescaler 1, while MPC83xx
* may have prescaler 1, 2, or 3, depending on the power-on
* configuration.
*/
u32 prescaler = 1;
/* mpc85xx */
if (pvr_version_is(PVR_VER_E500V1) || pvr_version_is(PVR_VER_E500V2)
|| pvr_version_is(PVR_VER_E500MC)
|| pvr_version_is(PVR_VER_E5500)
|| pvr_version_is(PVR_VER_E6500)) {
unsigned int svr = mfspr(SPRN_SVR);
if ((SVR_SOC_VER(svr) == SVR_8540)
|| (SVR_SOC_VER(svr) == SVR_8541)
|| (SVR_SOC_VER(svr) == SVR_8560)
|| (SVR_SOC_VER(svr) == SVR_8555)
|| (SVR_SOC_VER(svr) == SVR_8610))
/* the above 85xx SoCs have prescaler 1 */
prescaler = 1;
else if ((SVR_SOC_VER(svr) == SVR_8533)
|| (SVR_SOC_VER(svr) == SVR_8544))
/* the above 85xx SoCs have prescaler 3 or 2 */
prescaler = mpc_i2c_get_sec_cfg_8xxx() ? 3 : 2;
else
/* all the other 85xx have prescaler 2 */
prescaler = 2;
}
return prescaler;
}
static int mpc_i2c_get_fdr_8xxx(struct device_node *node, u32 clock,
u32 *real_clk)
{
const struct mpc_i2c_divider *div = NULL;
u32 prescaler = mpc_i2c_get_prescaler_8xxx();
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;
}
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 mpc_i2c_setup_8xxx(struct device_node *node,
struct mpc_i2c *i2c,
u32 clock)
{
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, &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 mpc_i2c_setup_8xxx(struct device_node *node,
struct mpc_i2c *i2c,
u32 clock)
{
}
#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,
.algo = &mpc_algo,
.timeout = HZ,
};
static const struct of_device_id mpc_i2c_of_match[];
static int 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;
struct resource res;
struct clk *clk;
int err;
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;
}
}
/*
* enable clock for the I2C peripheral (non fatal),
* keep a reference upon successful allocation
*/
clk = devm_clk_get(&op->dev, NULL);
if (!IS_ERR(clk)) {
err = clk_prepare_enable(clk);
if (err) {
dev_err(&op->dev, "failed to enable clock\n");
goto fail_request;
} else {
i2c->clk_per = clk;
}
}
if (of_property_read_bool(op->dev.of_node, "fsl,preserve-clocking")) {
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);
} else {
/* Backwards compatibility */
if (of_get_property(op->dev.of_node, "dfsrr", NULL))
mpc_i2c_setup_8xxx(op->dev.of_node, i2c, clock);
}
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);
platform_set_drvdata(op, i2c);
i2c->adap = mpc_ops;
of_address_to_resource(op->dev.of_node, 0, &res);
scnprintf(i2c->adap.name, sizeof(i2c->adap.name),
"MPC adapter at 0x%llx", (unsigned long long)res.start);
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)
goto fail_add;
return result;
fail_add:
if (i2c->clk_per)
clk_disable_unprepare(i2c->clk_per);
free_irq(i2c->irq, i2c);
fail_request:
irq_dispose_mapping(i2c->irq);
iounmap(i2c->base);
fail_map:
kfree(i2c);
return result;
};
static int fsl_i2c_remove(struct platform_device *op)
{
struct mpc_i2c *i2c = platform_get_drvdata(op);
i2c_del_adapter(&i2c->adap);
if (i2c->clk_per)
clk_disable_unprepare(i2c->clk_per);
if (i2c->irq)
free_irq(i2c->irq, i2c);
irq_dispose_mapping(i2c->irq);
iounmap(i2c->base);
kfree(i2c);
return 0;
};
#ifdef CONFIG_PM_SLEEP
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;
}
static SIMPLE_DEV_PM_OPS(mpc_i2c_pm_ops, mpc_i2c_suspend, mpc_i2c_resume);
#define MPC_I2C_PM_OPS (&mpc_i2c_pm_ops)
#else
#define MPC_I2C_PM_OPS NULL
#endif
static const struct mpc_i2c_data mpc_i2c_data_512x = {
.setup = mpc_i2c_setup_512x,
};
static const struct mpc_i2c_data mpc_i2c_data_52xx = {
.setup = mpc_i2c_setup_52xx,
};
static const struct mpc_i2c_data mpc_i2c_data_8313 = {
.setup = mpc_i2c_setup_8xxx,
};
static const struct mpc_i2c_data mpc_i2c_data_8543 = {
.setup = mpc_i2c_setup_8xxx,
};
static const struct mpc_i2c_data mpc_i2c_data_8544 = {
.setup = mpc_i2c_setup_8xxx,
};
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 = fsl_i2c_remove,
.driver = {
.name = DRV_NAME,
.of_match_table = mpc_i2c_of_match,
.pm = MPC_I2C_PM_OPS,
},
};
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