i2c-nforce2: Add support for SMBus block transactions

Add support for SMBus block read/write transactions to i2c-nforce2
driver, in particular to host controllers MCP51 and MCP55.

Signed-off-by: Oleg Ryjkov <olegr@google.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

1 files changed, 43 insertions, 1 deletions

diff --git a/drivers/i2c/busses/i2c-nforce2.c b/drivers/i2c/busses/i2c-nforce2.c
index 3cd0d63e7b50..c48140f782d0 100644
--- a/drivers/i2c/busses/i2c-nforce2.c
+++ b/drivers/i2c/busses/i2c-nforce2.c
@@ -61,6 +61,7 @@ struct nforce2_smbus {
         struct i2c_adapter adapter;
         int base;
         int size;
+        int blockops;
 };
 
 
@@ -80,6 +81,8 @@ struct nforce2_smbus {
 #define NVIDIA_SMB_ADDR         (smbus->base + 0x02)    /* address */
 #define NVIDIA_SMB_CMD          (smbus->base + 0x03)    /* command */
 #define NVIDIA_SMB_DATA         (smbus->base + 0x04)    /* 32 data registers */
+#define NVIDIA_SMB_BCNT         (smbus->base + 0x24)    /* number of data
+                                                           bytes */
 
 #define NVIDIA_SMB_STS_DONE     0x80
 #define NVIDIA_SMB_STS_ALRM     0x40
@@ -92,6 +95,7 @@ struct nforce2_smbus {
 #define NVIDIA_SMB_PRTCL_BYTE                   0x04
 #define NVIDIA_SMB_PRTCL_BYTE_DATA              0x06
 #define NVIDIA_SMB_PRTCL_WORD_DATA              0x08
+#define NVIDIA_SMB_PRTCL_BLOCK_DATA             0x0a
 #define NVIDIA_SMB_PRTCL_PEC                    0x80
 
 static struct pci_driver nforce2_driver;
@@ -103,6 +107,8 @@ static s32 nforce2_access(struct i2c_adapter * adap, u16 addr,
 {
         struct nforce2_smbus *smbus = adap->algo_data;
         unsigned char protocol, pec, temp;
+        u8 len;
+        int i;
 
         protocol = (read_write == I2C_SMBUS_READ) ? NVIDIA_SMB_PRTCL_READ :
                 NVIDIA_SMB_PRTCL_WRITE;
@@ -137,6 +143,25 @@ static s32 nforce2_access(struct i2c_adapter * adap, u16 addr,
                         protocol |= NVIDIA_SMB_PRTCL_WORD_DATA | pec;
                         break;
 
+                case I2C_SMBUS_BLOCK_DATA:
+                        outb_p(command, NVIDIA_SMB_CMD);
+                        if (read_write == I2C_SMBUS_WRITE) {
+                                len = data->block[0];
+                                if ((len == 0) || (len > I2C_SMBUS_BLOCK_MAX)) {
+                                        dev_err(&adap->dev,
+                                                "Transaction failed "
+                                                "(requested block size: %d)\n",
+                                                len);
+                                        return -1;
+                                }
+                                outb_p(len, NVIDIA_SMB_BCNT);
+                                for (i = 0; i < I2C_SMBUS_BLOCK_MAX; i++)
+                                        outb_p(data->block[i + 1],
+                                               NVIDIA_SMB_DATA+i);
+                        }
+                        protocol |= NVIDIA_SMB_PRTCL_BLOCK_DATA | pec;
+                        break;
+
                 default:
                         dev_err(&adap->dev, "Unsupported transaction %d\n", size);
                         return -1;
@@ -174,6 +199,14 @@ static s32 nforce2_access(struct i2c_adapter * adap, u16 addr,
                 case I2C_SMBUS_WORD_DATA:
                         data->word = inb_p(NVIDIA_SMB_DATA) | (inb_p(NVIDIA_SMB_DATA+1) << 8);
                         break;
+
+                case I2C_SMBUS_BLOCK_DATA:
+                        len = inb_p(NVIDIA_SMB_BCNT);
+                        len = min_t(u8, len, I2C_SMBUS_BLOCK_MAX);
+                        for (i = 0; i < len; i++)
+                                data->block[i+1] = inb_p(NVIDIA_SMB_DATA + i);
+                        data->block[0] = len;
+                        break;
         }
 
         return 0;
@@ -184,7 +217,9 @@ static u32 nforce2_func(struct i2c_adapter *adapter)
 {
         /* other functionality might be possible, but is not tested */
         return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
-            I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA;
+               I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
+               (((struct nforce2_smbus*)adapter->algo_data)->blockops ?
+                I2C_FUNC_SMBUS_BLOCK_DATA : 0);
 }
 
 static struct i2c_algorithm smbus_algorithm = {
@@ -268,6 +303,13 @@ static int __devinit nforce2_probe(struct pci_dev *dev, const struct pci_device_
                 return -ENOMEM;
         pci_set_drvdata(dev, smbuses);
 
+        switch(dev->device) {
+        case PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SMBUS:
+        case PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SMBUS:
+                smbuses[0].blockops = 1;
+                smbuses[1].blockops = 1;
+        }
+
         /* SMBus adapter 1 */
         res1 = nforce2_probe_smb(dev, 4, NFORCE_PCI_SMB1, &smbuses[0], "SMB1");
         if (res1 < 0) {