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>

diff --git a/drivers/i2c/busses/i2c-nforce2.c b/drivers/i2c/busses/i2c-nforce2.c
index 3cd0d63e7b501c047e04e52945211e988409b0a1..c48140f782d09c276dcb4c6b31d5201dd213b6dd 100644 (file)
--- 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) {