While writing any sequence or session identifiers, it is possible that the host could write a zero value, whereas only non-zero values are supported writes to those registers. Ensure that host does not write a non-zero value for those cases. Signed-off-by: Bhaumik Bhatt <bbhatt@xxxxxxxxxxxxxx> --- drivers/bus/mhi/core/boot.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/bus/mhi/core/boot.c b/drivers/bus/mhi/core/boot.c index 0bc9c50..c9971d4 100644 --- a/drivers/bus/mhi/core/boot.c +++ b/drivers/bus/mhi/core/boot.c @@ -199,6 +199,9 @@ static int mhi_fw_load_amss(struct mhi_controller *mhi_cntrl, mhi_write_reg(mhi_cntrl, base, BHIE_TXVECSIZE_OFFS, mhi_buf->len); sequence_id = prandom_u32() & BHIE_TXVECSTATUS_SEQNUM_BMSK; + if (unlikely(!sequence_id)) + sequence_id = 1; + mhi_write_reg_field(mhi_cntrl, base, BHIE_TXVECDB_OFFS, BHIE_TXVECDB_SEQNUM_BMSK, BHIE_TXVECDB_SEQNUM_SHFT, sequence_id); @@ -254,6 +257,9 @@ static int mhi_fw_load_sbl(struct mhi_controller *mhi_cntrl, lower_32_bits(dma_addr)); mhi_write_reg(mhi_cntrl, base, BHI_IMGSIZE, size); session_id = prandom_u32() & BHI_TXDB_SEQNUM_BMSK; + if (unlikely(!session_id)) + session_id = 1; + mhi_write_reg(mhi_cntrl, base, BHI_IMGTXDB, session_id); read_unlock_bh(pm_lock); -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project