diff options
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/tpm/tpm_crb.c | 39 |
1 files changed, 28 insertions, 11 deletions
diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c index 733cd0e20598..5afe6840030e 100644 --- a/drivers/char/tpm/tpm_crb.c +++ b/drivers/char/tpm/tpm_crb.c @@ -259,7 +259,10 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv, struct list_head resources; struct resource io_res; struct device *dev = &device->dev; - u64 pa; + u64 cmd_pa; + u32 cmd_size; + u64 rsp_pa; + u32 rsp_size; int ret; INIT_LIST_HEAD(&resources); @@ -280,22 +283,36 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv, return PTR_ERR(priv->iobase); priv->cca = crb_map_res(dev, priv, &io_res, buf->control_address, - 0x1000); + sizeof(struct crb_control_area)); if (IS_ERR(priv->cca)) return PTR_ERR(priv->cca); - pa = ((u64) ioread32(&priv->cca->cmd_pa_high) << 32) | - (u64) ioread32(&priv->cca->cmd_pa_low); - priv->cmd = crb_map_res(dev, priv, &io_res, pa, - ioread32(&priv->cca->cmd_size)); + cmd_pa = ((u64) ioread32(&priv->cca->cmd_pa_high) << 32) | + (u64) ioread32(&priv->cca->cmd_pa_low); + cmd_size = ioread32(&priv->cca->cmd_size); + priv->cmd = crb_map_res(dev, priv, &io_res, cmd_pa, cmd_size); if (IS_ERR(priv->cmd)) return PTR_ERR(priv->cmd); - memcpy_fromio(&pa, &priv->cca->rsp_pa, 8); - pa = le64_to_cpu(pa); - priv->rsp = crb_map_res(dev, priv, &io_res, pa, - ioread32(&priv->cca->rsp_size)); - return PTR_ERR_OR_ZERO(priv->rsp); + memcpy_fromio(&rsp_pa, &priv->cca->rsp_pa, 8); + rsp_pa = le64_to_cpu(rsp_pa); + rsp_size = ioread32(&priv->cca->rsp_size); + + if (cmd_pa != rsp_pa) { + priv->rsp = crb_map_res(dev, priv, &io_res, rsp_pa, rsp_size); + return PTR_ERR_OR_ZERO(priv->rsp); + } + + /* According to the PTP specification, overlapping command and response + * buffer sizes must be identical. + */ + if (cmd_size != rsp_size) { + dev_err(dev, FW_BUG "overlapping command and response buffer sizes are not identical"); + return -EINVAL; + } + + priv->rsp = priv->cmd; + return 0; } static int crb_acpi_add(struct acpi_device *device) |