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-rw-r--r--drivers/i2c/busses/Kconfig2
-rw-r--r--drivers/i2c/busses/i2c-sh_mobile.c121
-rw-r--r--drivers/i2c/i2c-core.c87
-rw-r--r--drivers/i2c/i2c-dev.c26
4 files changed, 149 insertions, 87 deletions
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index bceafbfa7268..29e01f6238a7 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -549,7 +549,7 @@ config I2C_SH7760
config I2C_SH_MOBILE
tristate "SuperH Mobile I2C Controller"
- depends on SUPERH
+ depends on SUPERH || ARCH_SHMOBILE
help
If you say yes to this option, support will be included for the
built-in I2C interface on the Renesas SH-Mobile processor.
diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c
index ffb405d7c6f2..598c49acaeb5 100644
--- a/drivers/i2c/busses/i2c-sh_mobile.c
+++ b/drivers/i2c/busses/i2c-sh_mobile.c
@@ -119,8 +119,10 @@ struct sh_mobile_i2c_data {
struct i2c_adapter adap;
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;
@@ -129,15 +131,17 @@ struct sh_mobile_i2c_data {
int sr;
};
+#define IIC_FLAG_HAS_ICIC67 (1 << 0)
+
#define NORMAL_SPEED 100000 /* FAST_SPEED 400000 */
/* Register offsets */
-#define ICDR(pd) (pd->reg + 0x00)
-#define ICCR(pd) (pd->reg + 0x04)
-#define ICSR(pd) (pd->reg + 0x08)
-#define ICIC(pd) (pd->reg + 0x0c)
-#define ICCL(pd) (pd->reg + 0x10)
-#define ICCH(pd) (pd->reg + 0x14)
+#define ICDR 0x00
+#define ICCR 0x04
+#define ICSR 0x08
+#define ICIC 0x0c
+#define ICCL 0x10
+#define ICCH 0x14
/* Register bits */
#define ICCR_ICE 0x80
@@ -155,11 +159,32 @@ struct sh_mobile_i2c_data {
#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;
@@ -187,6 +212,14 @@ static void activate_ch(struct sh_mobile_i2c_data *pd)
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;
@@ -196,25 +229,33 @@ static void activate_ch(struct sh_mobile_i2c_data *pd)
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 */
- iowrite8(ioread8(ICCR(pd)) | ICCR_ICE, ICCR(pd));
+ iic_set_clr(pd, ICCR, ICCR_ICE, 0);
/* Mask all interrupts */
- iowrite8(0, ICIC(pd));
+ iic_wr(pd, ICIC, 0);
/* Set the clock */
- iowrite8(pd->iccl, ICCL(pd));
- iowrite8(pd->icch, ICCH(pd));
+ 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 */
- iowrite8(0, ICSR(pd));
- iowrite8(0, ICIC(pd));
+ iic_wr(pd, ICSR, 0);
+ iic_wr(pd, ICIC, 0);
/* Disable channel */
- iowrite8(ioread8(ICCR(pd)) & ~ICCR_ICE, ICCR(pd));
+ iic_set_clr(pd, ICCR, 0, ICCR_ICE);
/* Disable clock and mark device as idle */
clk_disable(pd->clk);
@@ -233,35 +274,35 @@ static unsigned char i2c_op(struct sh_mobile_i2c_data *pd,
switch (op) {
case OP_START: /* issue start and trigger DTE interrupt */
- iowrite8(0x94, ICCR(pd));
+ iic_wr(pd, ICCR, 0x94);
break;
case OP_TX_FIRST: /* disable DTE interrupt and write data */
- iowrite8(ICIC_WAITE | ICIC_ALE | ICIC_TACKE, ICIC(pd));
- iowrite8(data, ICDR(pd));
+ iic_wr(pd, ICIC, ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
+ iic_wr(pd, ICDR, data);
break;
case OP_TX: /* write data */
- iowrite8(data, ICDR(pd));
+ iic_wr(pd, ICDR, data);
break;
case OP_TX_STOP: /* write data and issue a stop afterwards */
- iowrite8(data, ICDR(pd));
- iowrite8(0x90, ICCR(pd));
+ iic_wr(pd, ICDR, data);
+ iic_wr(pd, ICCR, 0x90);
break;
case OP_TX_TO_RX: /* select read mode */
- iowrite8(0x81, ICCR(pd));
+ iic_wr(pd, ICCR, 0x81);
break;
case OP_RX: /* just read data */
- ret = ioread8(ICDR(pd));
+ ret = iic_rd(pd, ICDR);
break;
case OP_RX_STOP: /* enable DTE interrupt, issue stop */
- iowrite8(ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE,
- ICIC(pd));
- iowrite8(0xc0, ICCR(pd));
+ 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 */
- iowrite8(ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE,
- ICIC(pd));
- ret = ioread8(ICDR(pd));
- iowrite8(0xc0, ICCR(pd));
+ iic_wr(pd, ICIC,
+ ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
+ ret = iic_rd(pd, ICDR);
+ iic_wr(pd, ICCR, 0xc0);
break;
}
@@ -367,7 +408,7 @@ static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id)
unsigned char sr;
int wakeup;
- sr = ioread8(ICSR(pd));
+ 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,
@@ -376,7 +417,7 @@ static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id)
if (sr & (ICSR_AL | ICSR_TACK)) {
/* don't interrupt transaction - continue to issue stop */
- iowrite8(sr & ~(ICSR_AL | ICSR_TACK), ICSR(pd));
+ 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);
@@ -384,7 +425,7 @@ static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id)
wakeup = sh_mobile_i2c_isr_tx(pd);
if (sr & ICSR_WAIT) /* TODO: add delay here to support slow acks */
- iowrite8(sr & ~ICSR_WAIT, ICSR(pd));
+ iic_wr(pd, ICSR, sr & ~ICSR_WAIT);
if (wakeup) {
pd->sr |= SW_DONE;
@@ -402,21 +443,21 @@ static int start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg)
}
/* Initialize channel registers */
- iowrite8(ioread8(ICCR(pd)) & ~ICCR_ICE, ICCR(pd));
+ iic_set_clr(pd, ICCR, 0, ICCR_ICE);
/* Enable channel and configure rx ack */
- iowrite8(ioread8(ICCR(pd)) | ICCR_ICE, ICCR(pd));
+ iic_set_clr(pd, ICCR, ICCR_ICE, 0);
/* Set the clock */
- iowrite8(pd->iccl, ICCL(pd));
- iowrite8(pd->icch, ICCH(pd));
+ 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 */
- iowrite8(ICIC_WAITE | ICIC_ALE | ICIC_TACKE | ICIC_DTEE, ICIC(pd));
+ iic_wr(pd, ICIC, ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
return 0;
}
@@ -451,7 +492,7 @@ static int sh_mobile_i2c_xfer(struct i2c_adapter *adapter,
retry_count = 1000;
again:
- val = ioread8(ICSR(pd));
+ val = iic_rd(pd, ICSR);
dev_dbg(pd->dev, "val 0x%02x pd->sr 0x%02x\n", val, pd->sr);
@@ -576,6 +617,12 @@ static int sh_mobile_i2c_probe(struct platform_device *dev)
goto err_irq;
}
+ /* 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
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 0815e10da7c6..6a9d9bb47073 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -424,6 +424,35 @@ static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr)
}
/**
+ * i2c_lock_adapter - Get exclusive access to an I2C bus segment
+ * @adapter: Target I2C bus segment
+ */
+void i2c_lock_adapter(struct i2c_adapter *adapter)
+{
+ rt_mutex_lock(&adapter->bus_lock);
+}
+EXPORT_SYMBOL_GPL(i2c_lock_adapter);
+
+/**
+ * i2c_trylock_adapter - Try to get exclusive access to an I2C bus segment
+ * @adapter: Target I2C bus segment
+ */
+static int i2c_trylock_adapter(struct i2c_adapter *adapter)
+{
+ return rt_mutex_trylock(&adapter->bus_lock);
+}
+
+/**
+ * i2c_unlock_adapter - Release exclusive access to an I2C bus segment
+ * @adapter: Target I2C bus segment
+ */
+void i2c_unlock_adapter(struct i2c_adapter *adapter)
+{
+ rt_mutex_unlock(&adapter->bus_lock);
+}
+EXPORT_SYMBOL_GPL(i2c_unlock_adapter);
+
+/**
* i2c_new_device - instantiate an i2c device
* @adap: the adapter managing the device
* @info: describes one I2C device; bus_num is ignored
@@ -754,7 +783,7 @@ static int __process_new_adapter(struct device_driver *d, void *data)
static int i2c_register_adapter(struct i2c_adapter *adap)
{
- int res = 0, dummy;
+ int res = 0;
/* Can't register until after driver model init */
if (unlikely(WARN_ON(!i2c_bus_type.p))) {
@@ -792,8 +821,7 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
/* Notify drivers */
mutex_lock(&core_lock);
- dummy = bus_for_each_drv(&i2c_bus_type, NULL, adap,
- __process_new_adapter);
+ bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter);
mutex_unlock(&core_lock);
return 0;
@@ -1229,12 +1257,12 @@ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
#endif
if (in_atomic() || irqs_disabled()) {
- ret = rt_mutex_trylock(&adap->bus_lock);
+ ret = i2c_trylock_adapter(adap);
if (!ret)
/* I2C activity is ongoing. */
return -EAGAIN;
} else {
- rt_mutex_lock(&adap->bus_lock);
+ i2c_lock_adapter(adap);
}
/* Retry automatically on arbitration loss */
@@ -1246,7 +1274,7 @@ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
if (time_after(jiffies, orig_jiffies + adap->timeout))
break;
}
- rt_mutex_unlock(&adap->bus_lock);
+ i2c_unlock_adapter(adap);
return ret;
} else {
@@ -1341,13 +1369,17 @@ static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr)
I2C_SMBUS_BYTE_DATA, &dummy);
else
#endif
- if ((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50
- || !i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK))
- err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0,
- I2C_SMBUS_BYTE, &dummy);
- else
+ if (!((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50)
+ && i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK))
err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0,
I2C_SMBUS_QUICK, NULL);
+ else if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE))
+ err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0,
+ I2C_SMBUS_BYTE, &dummy);
+ else {
+ dev_warn(&adap->dev, "No suitable probing method supported\n");
+ err = -EOPNOTSUPP;
+ }
return err >= 0;
}
@@ -1428,16 +1460,6 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver)
if (!(adapter->class & driver->class))
goto exit_free;
- /* Stop here if the bus doesn't support probing */
- if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE)) {
- if (address_list[0] == I2C_CLIENT_END)
- goto exit_free;
-
- dev_warn(&adapter->dev, "Probing not supported\n");
- err = -EOPNOTSUPP;
- goto exit_free;
- }
-
for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) {
dev_dbg(&adapter->dev, "found normal entry for adapter %d, "
"addr 0x%02x\n", adap_id, address_list[i]);
@@ -1452,18 +1474,23 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver)
return err;
}
+int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr)
+{
+ return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0,
+ I2C_SMBUS_QUICK, NULL) >= 0;
+}
+EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read);
+
struct i2c_client *
i2c_new_probed_device(struct i2c_adapter *adap,
struct i2c_board_info *info,
- unsigned short const *addr_list)
+ unsigned short const *addr_list,
+ int (*probe)(struct i2c_adapter *, unsigned short addr))
{
int i;
- /* Stop here if the bus doesn't support probing */
- if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) {
- dev_err(&adap->dev, "Probing not supported\n");
- return NULL;
- }
+ if (!probe)
+ probe = i2c_default_probe;
for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) {
/* Check address validity */
@@ -1481,7 +1508,7 @@ i2c_new_probed_device(struct i2c_adapter *adap,
}
/* Test address responsiveness */
- if (i2c_default_probe(adap, addr_list[i]))
+ if (probe(adap, addr_list[i]))
break;
}
@@ -1993,7 +2020,7 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags,
flags &= I2C_M_TEN | I2C_CLIENT_PEC;
if (adapter->algo->smbus_xfer) {
- rt_mutex_lock(&adapter->bus_lock);
+ i2c_lock_adapter(adapter);
/* Retry automatically on arbitration loss */
orig_jiffies = jiffies;
@@ -2007,7 +2034,7 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags,
orig_jiffies + adapter->timeout))
break;
}
- rt_mutex_unlock(&adapter->bus_lock);
+ i2c_unlock_adapter(adapter);
} else
res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write,
command, protocol, data);
diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
index e0694e4d86c7..0b0427f7d348 100644
--- a/drivers/i2c/i2c-dev.c
+++ b/drivers/i2c/i2c-dev.c
@@ -167,13 +167,9 @@ static ssize_t i2cdev_write(struct file *file, const char __user *buf,
if (count > 8192)
count = 8192;
- tmp = kmalloc(count, GFP_KERNEL);
- if (tmp == NULL)
- return -ENOMEM;
- if (copy_from_user(tmp, buf, count)) {
- kfree(tmp);
- return -EFAULT;
- }
+ tmp = memdup_user(buf, count);
+ if (IS_ERR(tmp))
+ return PTR_ERR(tmp);
pr_debug("i2c-dev: i2c-%d writing %zu bytes.\n",
iminor(file->f_path.dentry->d_inode), count);
@@ -219,9 +215,7 @@ static noinline int i2cdev_ioctl_rdrw(struct i2c_client *client,
if (rdwr_arg.nmsgs > I2C_RDRW_IOCTL_MAX_MSGS)
return -EINVAL;
- rdwr_pa = (struct i2c_msg *)
- kmalloc(rdwr_arg.nmsgs * sizeof(struct i2c_msg),
- GFP_KERNEL);
+ rdwr_pa = kmalloc(rdwr_arg.nmsgs * sizeof(struct i2c_msg), GFP_KERNEL);
if (!rdwr_pa)
return -ENOMEM;
@@ -247,15 +241,9 @@ static noinline int i2cdev_ioctl_rdrw(struct i2c_client *client,
break;
}
data_ptrs[i] = (u8 __user *)rdwr_pa[i].buf;
- rdwr_pa[i].buf = kmalloc(rdwr_pa[i].len, GFP_KERNEL);
- if (rdwr_pa[i].buf == NULL) {
- res = -ENOMEM;
- break;
- }
- if (copy_from_user(rdwr_pa[i].buf, data_ptrs[i],
- rdwr_pa[i].len)) {
- ++i; /* Needs to be kfreed too */
- res = -EFAULT;
+ rdwr_pa[i].buf = memdup_user(data_ptrs[i], rdwr_pa[i].len);
+ if (IS_ERR(rdwr_pa[i].buf)) {
+ res = PTR_ERR(rdwr_pa[i].buf);
break;
}
}