diff options
| author | Jeffrey Hugo <quic_jhugo@quicinc.com> | 2024-02-19 11:07:48 -0700 |
|---|---|---|
| committer | Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> | 2024-02-21 11:22:25 +0530 |
| commit | f0397e27d1204a7e6581d140c2de7fd11383c6ba (patch) | |
| tree | 88c064c97f53505cd2c900feb72f3744cb60d014 /drivers/bus/mhi/host/init.c | |
| parent | ceeb64f41fe6a1eb9fc56d583983a81f8f3dd058 (diff) | |
Revert "bus: mhi: core: Add support for reading MHI info from device"
This reverts commit 3316ab2b45f6bf4797d8d65b22fda3cc13318890.
The MHI spec owner pointed out that the SOC_HW_VERSION register is part
of the BHIe segment, and only valid on devices which implement BHIe.
Only a small subset of MHI devices implement BHIe so blindly accessing
the register for all devices is not correct. Also, since the BHIe
segment offset is not used when accessing the register, any
implementation which moves the BHIe segment will result in accessing
some other register. We've seen that accessing this register on AIC100
which does not support BHIe can result in initialization failures.
We could try to put checks into the code to address these issues, but in
the roughly 4 years this functionality has existed, no one has used it.
Easier to drop this dead code and address the issues if anyone comes up
with a real world use for it.
Signed-off-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20240219180748.1591527-1-quic_jhugo@quicinc.com
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Diffstat (limited to 'drivers/bus/mhi/host/init.c')
| -rw-r--r-- | drivers/bus/mhi/host/init.c | 12 |
1 files changed, 0 insertions, 12 deletions
diff --git a/drivers/bus/mhi/host/init.c b/drivers/bus/mhi/host/init.c index 944da46e6f11..44f934981de8 100644 --- a/drivers/bus/mhi/host/init.c +++ b/drivers/bus/mhi/host/init.c @@ -914,7 +914,6 @@ int mhi_register_controller(struct mhi_controller *mhi_cntrl, struct mhi_chan *mhi_chan; struct mhi_cmd *mhi_cmd; struct mhi_device *mhi_dev; - u32 soc_info; int ret, i; if (!mhi_cntrl || !mhi_cntrl->cntrl_dev || !mhi_cntrl->regs || @@ -989,17 +988,6 @@ int mhi_register_controller(struct mhi_controller *mhi_cntrl, mhi_cntrl->unmap_single = mhi_unmap_single_no_bb; } - /* Read the MHI device info */ - ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->regs, - SOC_HW_VERSION_OFFS, &soc_info); - if (ret) - goto err_destroy_wq; - - mhi_cntrl->family_number = FIELD_GET(SOC_HW_VERSION_FAM_NUM_BMSK, soc_info); - mhi_cntrl->device_number = FIELD_GET(SOC_HW_VERSION_DEV_NUM_BMSK, soc_info); - mhi_cntrl->major_version = FIELD_GET(SOC_HW_VERSION_MAJOR_VER_BMSK, soc_info); - mhi_cntrl->minor_version = FIELD_GET(SOC_HW_VERSION_MINOR_VER_BMSK, soc_info); - mhi_cntrl->index = ida_alloc(&mhi_controller_ida, GFP_KERNEL); if (mhi_cntrl->index < 0) { ret = mhi_cntrl->index; |