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path: root/drivers/char/tpm/tpm_tis_spi.c
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Diffstat (limited to 'drivers/char/tpm/tpm_tis_spi.c')
-rw-r--r--drivers/char/tpm/tpm_tis_spi.c73
1 files changed, 45 insertions, 28 deletions
diff --git a/drivers/char/tpm/tpm_tis_spi.c b/drivers/char/tpm/tpm_tis_spi.c
index 88fe72ae967f..424ff2fde1f2 100644
--- a/drivers/char/tpm/tpm_tis_spi.c
+++ b/drivers/char/tpm/tpm_tis_spi.c
@@ -46,9 +46,7 @@
struct tpm_tis_spi_phy {
struct tpm_tis_data priv;
struct spi_device *spi_device;
-
- u8 tx_buf[4];
- u8 rx_buf[4];
+ u8 *iobuf;
};
static inline struct tpm_tis_spi_phy *to_tpm_tis_spi_phy(struct tpm_tis_data *data)
@@ -57,7 +55,7 @@ static inline struct tpm_tis_spi_phy *to_tpm_tis_spi_phy(struct tpm_tis_data *da
}
static int tpm_tis_spi_transfer(struct tpm_tis_data *data, u32 addr, u16 len,
- u8 *buffer, u8 direction)
+ u8 *in, const u8 *out)
{
struct tpm_tis_spi_phy *phy = to_tpm_tis_spi_phy(data);
int ret = 0;
@@ -71,14 +69,14 @@ static int tpm_tis_spi_transfer(struct tpm_tis_data *data, u32 addr, u16 len,
while (len) {
transfer_len = min_t(u16, len, MAX_SPI_FRAMESIZE);
- phy->tx_buf[0] = direction | (transfer_len - 1);
- phy->tx_buf[1] = 0xd4;
- phy->tx_buf[2] = addr >> 8;
- phy->tx_buf[3] = addr;
+ phy->iobuf[0] = (in ? 0x80 : 0) | (transfer_len - 1);
+ phy->iobuf[1] = 0xd4;
+ phy->iobuf[2] = addr >> 8;
+ phy->iobuf[3] = addr;
memset(&spi_xfer, 0, sizeof(spi_xfer));
- spi_xfer.tx_buf = phy->tx_buf;
- spi_xfer.rx_buf = phy->rx_buf;
+ spi_xfer.tx_buf = phy->iobuf;
+ spi_xfer.rx_buf = phy->iobuf;
spi_xfer.len = 4;
spi_xfer.cs_change = 1;
@@ -88,9 +86,9 @@ static int tpm_tis_spi_transfer(struct tpm_tis_data *data, u32 addr, u16 len,
if (ret < 0)
goto exit;
- if ((phy->rx_buf[3] & 0x01) == 0) {
+ if ((phy->iobuf[3] & 0x01) == 0) {
// handle SPI wait states
- phy->tx_buf[0] = 0;
+ phy->iobuf[0] = 0;
for (i = 0; i < TPM_RETRY; i++) {
spi_xfer.len = 1;
@@ -99,7 +97,7 @@ static int tpm_tis_spi_transfer(struct tpm_tis_data *data, u32 addr, u16 len,
ret = spi_sync_locked(phy->spi_device, &m);
if (ret < 0)
goto exit;
- if (phy->rx_buf[0] & 0x01)
+ if (phy->iobuf[0] & 0x01)
break;
}
@@ -113,12 +111,12 @@ static int tpm_tis_spi_transfer(struct tpm_tis_data *data, u32 addr, u16 len,
spi_xfer.len = transfer_len;
spi_xfer.delay_usecs = 5;
- if (direction) {
+ if (in) {
spi_xfer.tx_buf = NULL;
- spi_xfer.rx_buf = buffer;
- } else {
- spi_xfer.tx_buf = buffer;
+ } else if (out) {
spi_xfer.rx_buf = NULL;
+ memcpy(phy->iobuf, out, transfer_len);
+ out += transfer_len;
}
spi_message_init(&m);
@@ -127,8 +125,12 @@ static int tpm_tis_spi_transfer(struct tpm_tis_data *data, u32 addr, u16 len,
if (ret < 0)
goto exit;
+ if (in) {
+ memcpy(in, phy->iobuf, transfer_len);
+ in += transfer_len;
+ }
+
len -= transfer_len;
- buffer += transfer_len;
}
exit:
@@ -139,40 +141,51 @@ exit:
static int tpm_tis_spi_read_bytes(struct tpm_tis_data *data, u32 addr,
u16 len, u8 *result)
{
- return tpm_tis_spi_transfer(data, addr, len, result, 0x80);
+ return tpm_tis_spi_transfer(data, addr, len, result, NULL);
}
static int tpm_tis_spi_write_bytes(struct tpm_tis_data *data, u32 addr,
- u16 len, u8 *value)
+ u16 len, const u8 *value)
{
- return tpm_tis_spi_transfer(data, addr, len, value, 0);
+ return tpm_tis_spi_transfer(data, addr, len, NULL, value);
}
static int tpm_tis_spi_read16(struct tpm_tis_data *data, u32 addr, u16 *result)
{
+ __le16 result_le;
int rc;
- rc = data->phy_ops->read_bytes(data, addr, sizeof(u16), (u8 *)result);
+ rc = data->phy_ops->read_bytes(data, addr, sizeof(u16),
+ (u8 *)&result_le);
if (!rc)
- *result = le16_to_cpu(*result);
+ *result = le16_to_cpu(result_le);
+
return rc;
}
static int tpm_tis_spi_read32(struct tpm_tis_data *data, u32 addr, u32 *result)
{
+ __le32 result_le;
int rc;
- rc = data->phy_ops->read_bytes(data, addr, sizeof(u32), (u8 *)result);
+ rc = data->phy_ops->read_bytes(data, addr, sizeof(u32),
+ (u8 *)&result_le);
if (!rc)
- *result = le32_to_cpu(*result);
+ *result = le32_to_cpu(result_le);
+
return rc;
}
static int tpm_tis_spi_write32(struct tpm_tis_data *data, u32 addr, u32 value)
{
- value = cpu_to_le32(value);
- return data->phy_ops->write_bytes(data, addr, sizeof(u32),
- (u8 *)&value);
+ __le32 value_le;
+ int rc;
+
+ value_le = cpu_to_le32(value);
+ rc = data->phy_ops->write_bytes(data, addr, sizeof(u32),
+ (u8 *)&value_le);
+
+ return rc;
}
static const struct tpm_tis_phy_ops tpm_spi_phy_ops = {
@@ -194,6 +207,10 @@ static int tpm_tis_spi_probe(struct spi_device *dev)
phy->spi_device = dev;
+ phy->iobuf = devm_kmalloc(&dev->dev, MAX_SPI_FRAMESIZE, GFP_KERNEL);
+ if (!phy->iobuf)
+ return -ENOMEM;
+
return tpm_tis_core_init(&dev->dev, &phy->priv, -1, &tpm_spi_phy_ops,
NULL);
}