linux/drivers/i2c/busses/i2c-sh_mobile.c

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/*
* SuperH Mobile I2C Controller
*
* Copyright (C) 2008 Magnus Damm
*
* Portions of the code based on out-of-tree driver i2c-sh7343.c
* Copyright (c) 2006 Carlos Munoz <carlos@kenati.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/i2c.h>
#include <linux/err.h>
#include <linux/pm_runtime.h>
#include <linux/clk.h>
#include <linux/io.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#include <linux/i2c/i2c-sh_mobile.h>
/* Transmit operation: */
/* */
/* 0 byte transmit */
/* BUS: S A8 ACK P */
/* IRQ: DTE WAIT */
/* ICIC: */
/* ICCR: 0x94 0x90 */
/* ICDR: A8 */
/* */
/* 1 byte transmit */
/* BUS: S A8 ACK D8(1) ACK P */
/* IRQ: DTE WAIT WAIT */
/* ICIC: -DTE */
/* ICCR: 0x94 0x90 */
/* ICDR: A8 D8(1) */
/* */
/* 2 byte transmit */
/* BUS: S A8 ACK D8(1) ACK D8(2) ACK P */
/* IRQ: DTE WAIT WAIT WAIT */
/* ICIC: -DTE */
/* ICCR: 0x94 0x90 */
/* ICDR: A8 D8(1) D8(2) */
/* */
/* 3 bytes or more, +---------+ gets repeated */
/* */
/* */
/* Receive operation: */
/* */
/* 0 byte receive - not supported since slave may hold SDA low */
/* */
/* 1 byte receive [TX] | [RX] */
/* BUS: S A8 ACK | D8(1) ACK P */
/* IRQ: DTE WAIT | WAIT DTE */
/* ICIC: -DTE | +DTE */
/* ICCR: 0x94 0x81 | 0xc0 */
/* ICDR: A8 | D8(1) */
/* */
/* 2 byte receive [TX]| [RX] */
/* BUS: S A8 ACK | D8(1) ACK D8(2) ACK P */
/* IRQ: DTE WAIT | WAIT WAIT DTE */
/* ICIC: -DTE | +DTE */
/* ICCR: 0x94 0x81 | 0xc0 */
/* ICDR: A8 | D8(1) D8(2) */
/* */
/* 3 byte receive [TX] | [RX] */
/* BUS: S A8 ACK | D8(1) ACK D8(2) ACK D8(3) ACK P */
/* IRQ: DTE WAIT | WAIT WAIT WAIT DTE */
/* ICIC: -DTE | +DTE */
/* ICCR: 0x94 0x81 | 0xc0 */
/* ICDR: A8 | D8(1) D8(2) D8(3) */
/* */
/* 4 bytes or more, this part is repeated +---------+ */
/* */
/* */
/* Interrupt order and BUSY flag */
/* ___ _ */
/* SDA ___\___XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXAAAAAAAAA___/ */
/* SCL \_/1\_/2\_/3\_/4\_/5\_/6\_/7\_/8\___/9\_____/ */
/* */
/* S D7 D6 D5 D4 D3 D2 D1 D0 P */
/* ___ */
/* WAIT IRQ ________________________________/ \___________ */
/* TACK IRQ ____________________________________/ \_______ */
/* DTE IRQ __________________________________________/ \_ */
/* AL IRQ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */
/* _______________________________________________ */
/* BUSY __/ \_ */
/* */
enum sh_mobile_i2c_op {
OP_START = 0,
OP_TX_FIRST,
OP_TX,
OP_TX_STOP,
OP_TX_TO_RX,
OP_RX,
OP_RX_STOP,
OP_RX_STOP_DATA,
};
struct sh_mobile_i2c_data {
struct device *dev;
void __iomem *reg;
struct i2c_adapter adap;
unsigned long bus_speed;
struct clk *clk;
u_int8_t icic;
u_int8_t iccl;
u_int8_t icch;
u_int8_t flags;
spinlock_t lock;
wait_queue_head_t wait;
struct i2c_msg *msg;
int pos;
int sr;
};
#define IIC_FLAG_HAS_ICIC67 (1 << 0)
#define NORMAL_SPEED 100000 /* FAST_SPEED 400000 */
/* Register offsets */
#define ICDR 0x00
#define ICCR 0x04
#define ICSR 0x08
#define ICIC 0x0c
#define ICCL 0x10
#define ICCH 0x14
/* Register bits */
#define ICCR_ICE 0x80
#define ICCR_RACK 0x40
#define ICCR_TRS 0x10
#define ICCR_BBSY 0x04
#define ICCR_SCP 0x01
#define ICSR_SCLM 0x80
#define ICSR_SDAM 0x40
#define SW_DONE 0x20
#define ICSR_BUSY 0x10
#define ICSR_AL 0x08
#define ICSR_TACK 0x04
#define ICSR_WAIT 0x02
#define ICSR_DTE 0x01
#define ICIC_ICCLB8 0x80
#define ICIC_ICCHB8 0x40
#define ICIC_ALE 0x08
#define ICIC_TACKE 0x04
#define ICIC_WAITE 0x02
#define ICIC_DTEE 0x01
static void iic_wr(struct sh_mobile_i2c_data *pd, int offs, unsigned char data)
{
if (offs == ICIC)
data |= pd->icic;
iowrite8(data, pd->reg + offs);
}
static unsigned char iic_rd(struct sh_mobile_i2c_data *pd, int offs)
{
return ioread8(pd->reg + offs);
}
static void iic_set_clr(struct sh_mobile_i2c_data *pd, int offs,
unsigned char set, unsigned char clr)
{
iic_wr(pd, offs, (iic_rd(pd, offs) | set) & ~clr);
}
static void activate_ch(struct sh_mobile_i2c_data *pd)
{
unsigned long i2c_clk;
u_int32_t num;
u_int32_t denom;
u_int32_t tmp;
/* Wake up device and enable clock */
pm_runtime_get_sync(pd->dev);
clk_enable(pd->clk);
/* Get clock rate after clock is enabled */
i2c_clk = clk_get_rate(pd->clk);
/* Calculate the value for iccl. From the data sheet:
* iccl = (p clock / transfer rate) * (L / (L + H))
* where L and H are the SCL low/high ratio (5/4 in this case).
* We also round off the result.
*/
num = i2c_clk * 5;
denom = pd->bus_speed * 9;
tmp = num * 10 / denom;
if (tmp % 10 >= 5)
pd->iccl = (u_int8_t)((num/denom) + 1);
else
pd->iccl = (u_int8_t)(num/denom);
/* one more bit of ICCL in ICIC */
if (pd->flags & IIC_FLAG_HAS_ICIC67) {
if ((num/denom) > 0xff)
pd->icic |= ICIC_ICCLB8;
else
pd->icic &= ~ICIC_ICCLB8;
}
/* Calculate the value for icch. From the data sheet:
icch = (p clock / transfer rate) * (H / (L + H)) */
num = i2c_clk * 4;
tmp = num * 10 / denom;
if (tmp % 10 >= 5)
pd->icch = (u_int8_t)((num/denom) + 1);
else
pd->icch = (u_int8_t)(num/denom);
/* one more bit of ICCH in ICIC */
if (pd->flags & IIC_FLAG_HAS_ICIC67) {
if ((num/denom) > 0xff)
pd->icic |= ICIC_ICCHB8;
else
pd->icic &= ~ICIC_ICCHB8;
}
/* Enable channel and configure rx ack */
iic_set_clr(pd, ICCR, ICCR_ICE, 0);
/* Mask all interrupts */
iic_wr(pd, ICIC, 0);
/* Set the clock */
iic_wr(pd, ICCL, pd->iccl);
iic_wr(pd, ICCH, pd->icch);
}
static void deactivate_ch(struct sh_mobile_i2c_data *pd)
{
/* Clear/disable interrupts */
iic_wr(pd, ICSR, 0);
iic_wr(pd, ICIC, 0);
/* Disable channel */
iic_set_clr(pd, ICCR, 0, ICCR_ICE);
/* Disable clock and mark device as idle */
clk_disable(pd->clk);
pm_runtime_put_sync(pd->dev);
}
static unsigned char i2c_op(struct sh_mobile_i2c_data *pd,
enum sh_mobile_i2c_op op, unsigned char data)
{
unsigned char ret = 0;
unsigned long flags;
dev_dbg(pd->dev, "op %d, data in 0x%02x\n", op, data);
spin_lock_irqsave(&pd->lock, flags);
switch (op) {
case OP_START: /* issue start and trigger DTE interrupt */
iic_wr(pd, ICCR, 0x94);
break;
case OP_TX_FIRST: /* disable DTE interrupt and write data */
iic_wr(pd, ICIC, ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
iic_wr(pd, ICDR, data);
break;
case OP_TX: /* write data */
iic_wr(pd, ICDR, data);
break;
case OP_TX_STOP: /* write data and issue a stop afterwards */
iic_wr(pd, ICDR, data);
iic_wr(pd, ICCR, 0x90);
break;
case OP_TX_TO_RX: /* select read mode */
iic_wr(pd, ICCR, 0x81);
break;
case OP_RX: /* just read data */
ret = iic_rd(pd, ICDR);
break;
case OP_RX_STOP: /* enable DTE interrupt, issue stop */
iic_wr(pd, ICIC,
ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
iic_wr(pd, ICCR, 0xc0);
break;
case OP_RX_STOP_DATA: /* enable DTE interrupt, read data, issue stop */
iic_wr(pd, ICIC,
ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
ret = iic_rd(pd, ICDR);
iic_wr(pd, ICCR, 0xc0);
break;
}
spin_unlock_irqrestore(&pd->lock, flags);
dev_dbg(pd->dev, "op %d, data out 0x%02x\n", op, ret);
return ret;
}
static int sh_mobile_i2c_is_first_byte(struct sh_mobile_i2c_data *pd)
{
if (pd->pos == -1)
return 1;
return 0;
}
static int sh_mobile_i2c_is_last_byte(struct sh_mobile_i2c_data *pd)
{
if (pd->pos == (pd->msg->len - 1))
return 1;
return 0;
}
static void sh_mobile_i2c_get_data(struct sh_mobile_i2c_data *pd,
unsigned char *buf)
{
switch (pd->pos) {
case -1:
*buf = (pd->msg->addr & 0x7f) << 1;
*buf |= (pd->msg->flags & I2C_M_RD) ? 1 : 0;
break;
default:
*buf = pd->msg->buf[pd->pos];
}
}
static int sh_mobile_i2c_isr_tx(struct sh_mobile_i2c_data *pd)
{
unsigned char data;
if (pd->pos == pd->msg->len)
return 1;
sh_mobile_i2c_get_data(pd, &data);
if (sh_mobile_i2c_is_last_byte(pd))
i2c_op(pd, OP_TX_STOP, data);
else if (sh_mobile_i2c_is_first_byte(pd))
i2c_op(pd, OP_TX_FIRST, data);
else
i2c_op(pd, OP_TX, data);
pd->pos++;
return 0;
}
static int sh_mobile_i2c_isr_rx(struct sh_mobile_i2c_data *pd)
{
unsigned char data;
int real_pos;
do {
if (pd->pos <= -1) {
sh_mobile_i2c_get_data(pd, &data);
if (sh_mobile_i2c_is_first_byte(pd))
i2c_op(pd, OP_TX_FIRST, data);
else
i2c_op(pd, OP_TX, data);
break;
}
if (pd->pos == 0) {
i2c_op(pd, OP_TX_TO_RX, 0);
break;
}
real_pos = pd->pos - 2;
if (pd->pos == pd->msg->len) {
if (real_pos < 0) {
i2c_op(pd, OP_RX_STOP, 0);
break;
}
data = i2c_op(pd, OP_RX_STOP_DATA, 0);
} else
data = i2c_op(pd, OP_RX, 0);
if (real_pos >= 0)
pd->msg->buf[real_pos] = data;
} while (0);
pd->pos++;
return pd->pos == (pd->msg->len + 2);
}
static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id)
{
struct platform_device *dev = dev_id;
struct sh_mobile_i2c_data *pd = platform_get_drvdata(dev);
unsigned char sr;
int wakeup;
sr = iic_rd(pd, ICSR);
pd->sr |= sr; /* remember state */
dev_dbg(pd->dev, "i2c_isr 0x%02x 0x%02x %s %d %d!\n", sr, pd->sr,
(pd->msg->flags & I2C_M_RD) ? "read" : "write",
pd->pos, pd->msg->len);
if (sr & (ICSR_AL | ICSR_TACK)) {
/* don't interrupt transaction - continue to issue stop */
iic_wr(pd, ICSR, sr & ~(ICSR_AL | ICSR_TACK));
wakeup = 0;
} else if (pd->msg->flags & I2C_M_RD)
wakeup = sh_mobile_i2c_isr_rx(pd);
else
wakeup = sh_mobile_i2c_isr_tx(pd);
if (sr & ICSR_WAIT) /* TODO: add delay here to support slow acks */
iic_wr(pd, ICSR, sr & ~ICSR_WAIT);
if (wakeup) {
pd->sr |= SW_DONE;
wake_up(&pd->wait);
}
return IRQ_HANDLED;
}
static int start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg)
{
if (usr_msg->len == 0 && (usr_msg->flags & I2C_M_RD)) {
dev_err(pd->dev, "Unsupported zero length i2c read\n");
return -EIO;
}
/* Initialize channel registers */
iic_set_clr(pd, ICCR, 0, ICCR_ICE);
/* Enable channel and configure rx ack */
iic_set_clr(pd, ICCR, ICCR_ICE, 0);
/* Set the clock */
iic_wr(pd, ICCL, pd->iccl);
iic_wr(pd, ICCH, pd->icch);
pd->msg = usr_msg;
pd->pos = -1;
pd->sr = 0;
/* Enable all interrupts to begin with */
iic_wr(pd, ICIC, ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
return 0;
}
static int sh_mobile_i2c_xfer(struct i2c_adapter *adapter,
struct i2c_msg *msgs,
int num)
{
struct sh_mobile_i2c_data *pd = i2c_get_adapdata(adapter);
struct i2c_msg *msg;
int err = 0;
u_int8_t val;
int i, k, retry_count;
activate_ch(pd);
/* Process all messages */
for (i = 0; i < num; i++) {
msg = &msgs[i];
err = start_ch(pd, msg);
if (err)
break;
i2c_op(pd, OP_START, 0);
/* The interrupt handler takes care of the rest... */
k = wait_event_timeout(pd->wait,
pd->sr & (ICSR_TACK | SW_DONE),
5 * HZ);
if (!k)
dev_err(pd->dev, "Transfer request timed out\n");
retry_count = 1000;
again:
val = iic_rd(pd, ICSR);
dev_dbg(pd->dev, "val 0x%02x pd->sr 0x%02x\n", val, pd->sr);
/* the interrupt handler may wake us up before the
* transfer is finished, so poll the hardware
* until we're done.
*/
if (val & ICSR_BUSY) {
udelay(10);
if (retry_count--)
goto again;
err = -EIO;
dev_err(pd->dev, "Polling timed out\n");
break;
}
/* handle missing acknowledge and arbitration lost */
if ((val | pd->sr) & (ICSR_TACK | ICSR_AL)) {
err = -EIO;
break;
}
}
deactivate_ch(pd);
if (!err)
err = num;
return err;
}
static u32 sh_mobile_i2c_func(struct i2c_adapter *adapter)
{
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
}
static struct i2c_algorithm sh_mobile_i2c_algorithm = {
.functionality = sh_mobile_i2c_func,
.master_xfer = sh_mobile_i2c_xfer,
};
static int sh_mobile_i2c_hook_irqs(struct platform_device *dev, int hook)
{
struct resource *res;
int ret = -ENXIO;
int n, k = 0;
while ((res = platform_get_resource(dev, IORESOURCE_IRQ, k))) {
for (n = res->start; hook && n <= res->end; n++) {
if (request_irq(n, sh_mobile_i2c_isr, IRQF_DISABLED,
dev_name(&dev->dev), dev)) {
for (n--; n >= res->start; n--)
free_irq(n, dev);
goto rollback;
}
}
k++;
}
if (hook)
return k > 0 ? 0 : -ENOENT;
ret = 0;
rollback:
k--;
while (k >= 0) {
res = platform_get_resource(dev, IORESOURCE_IRQ, k);
for (n = res->start; n <= res->end; n++)
free_irq(n, dev);
k--;
}
return ret;
}
static int sh_mobile_i2c_probe(struct platform_device *dev)
{
struct i2c_sh_mobile_platform_data *pdata = dev->dev.platform_data;
struct sh_mobile_i2c_data *pd;
struct i2c_adapter *adap;
struct resource *res;
int size;
int ret;
pd = kzalloc(sizeof(struct sh_mobile_i2c_data), GFP_KERNEL);
if (pd == NULL) {
dev_err(&dev->dev, "cannot allocate private data\n");
return -ENOMEM;
}
pd->clk = clk_get(&dev->dev, NULL);
if (IS_ERR(pd->clk)) {
dev_err(&dev->dev, "cannot get clock\n");
ret = PTR_ERR(pd->clk);
goto err;
}
ret = sh_mobile_i2c_hook_irqs(dev, 1);
if (ret) {
dev_err(&dev->dev, "cannot request IRQ\n");
goto err_clk;
}
pd->dev = &dev->dev;
platform_set_drvdata(dev, pd);
res = platform_get_resource(dev, IORESOURCE_MEM, 0);
if (res == NULL) {
dev_err(&dev->dev, "cannot find IO resource\n");
ret = -ENOENT;
goto err_irq;
}
size = resource_size(res);
pd->reg = ioremap(res->start, size);
if (pd->reg == NULL) {
dev_err(&dev->dev, "cannot map IO\n");
ret = -ENXIO;
goto err_irq;
}
/* Use platformd data bus speed or NORMAL_SPEED */
pd->bus_speed = NORMAL_SPEED;
if (pdata && pdata->bus_speed)
pd->bus_speed = pdata->bus_speed;
/* The IIC blocks on SH-Mobile ARM processors
* come with two new bits in ICIC.
*/
if (size > 0x17)
pd->flags |= IIC_FLAG_HAS_ICIC67;
/* Enable Runtime PM for this device.
*
* Also tell the Runtime PM core to ignore children
* for this device since it is valid for us to suspend
* this I2C master driver even though the slave devices
* on the I2C bus may not be suspended.
*
* The state of the I2C hardware bus is unaffected by
* the Runtime PM state.
*/
pm_suspend_ignore_children(&dev->dev, true);
pm_runtime_enable(&dev->dev);
/* setup the private data */
adap = &pd->adap;
i2c_set_adapdata(adap, pd);
adap->owner = THIS_MODULE;
adap->algo = &sh_mobile_i2c_algorithm;
adap->dev.parent = &dev->dev;
adap->retries = 5;
adap->nr = dev->id;
strlcpy(adap->name, dev->name, sizeof(adap->name));
spin_lock_init(&pd->lock);
init_waitqueue_head(&pd->wait);
ret = i2c_add_numbered_adapter(adap);
if (ret < 0) {
dev_err(&dev->dev, "cannot add numbered adapter\n");
goto err_all;
}
dev_info(&dev->dev, "I2C adapter %d with bus speed %lu Hz\n",
adap->nr, pd->bus_speed);
return 0;
err_all:
iounmap(pd->reg);
err_irq:
sh_mobile_i2c_hook_irqs(dev, 0);
err_clk:
clk_put(pd->clk);
err:
kfree(pd);
return ret;
}
static int sh_mobile_i2c_remove(struct platform_device *dev)
{
struct sh_mobile_i2c_data *pd = platform_get_drvdata(dev);
i2c_del_adapter(&pd->adap);
iounmap(pd->reg);
sh_mobile_i2c_hook_irqs(dev, 0);
clk_put(pd->clk);
pm_runtime_disable(&dev->dev);
kfree(pd);
return 0;
}
static int sh_mobile_i2c_runtime_nop(struct device *dev)
{
/* Runtime PM callback shared between ->runtime_suspend()
* and ->runtime_resume(). Simply returns success.
*
* This driver re-initializes all registers after
* pm_runtime_get_sync() anyway so there is no need
* to save and restore registers here.
*/
return 0;
}
static const struct dev_pm_ops sh_mobile_i2c_dev_pm_ops = {
.runtime_suspend = sh_mobile_i2c_runtime_nop,
.runtime_resume = sh_mobile_i2c_runtime_nop,
};
static struct platform_driver sh_mobile_i2c_driver = {
.driver = {
.name = "i2c-sh_mobile",
.owner = THIS_MODULE,
.pm = &sh_mobile_i2c_dev_pm_ops,
},
.probe = sh_mobile_i2c_probe,
.remove = sh_mobile_i2c_remove,
};
static int __init sh_mobile_i2c_adap_init(void)
{
return platform_driver_register(&sh_mobile_i2c_driver);
}
static void __exit sh_mobile_i2c_adap_exit(void)
{
platform_driver_unregister(&sh_mobile_i2c_driver);
}
subsys_initcall(sh_mobile_i2c_adap_init);
module_exit(sh_mobile_i2c_adap_exit);
MODULE_DESCRIPTION("SuperH Mobile I2C Bus Controller driver");
MODULE_AUTHOR("Magnus Damm");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:i2c-sh_mobile");