bus: mhi: pci_generic: Apply no-op for wake using sideband wake boolean

Devices such as SDX24 do not have the provision for inband wake
doorbell in the form of channel 127 and instead have a sideband
GPIO for it. Newer devices such as SDX55 or SDX65 support inband
wake method by default. Ensure the functionality is used based on
this such that device wake stays held when a client driver uses
mhi_device_get() API or the equivalent debugfs entry.

Link: https://lore.kernel.org/r/1624560809-30610-1-git-send-email-bbhatt@codeaurora.org
Fixes: e3e5e6508fc1 ("bus: mhi: pci_generic: No-Op for device_wake operations")
Cc: stable@vger.kernel.org #5.12
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20210716075106.49938-2-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/bus/mhi/pci_generic.c b/drivers/bus/mhi/pci_generic.c
index ca3bc40..3396cb3 100644
--- a/drivers/bus/mhi/pci_generic.c
+++ b/drivers/bus/mhi/pci_generic.c
@@ -32,6 +32,8 @@
  * @edl: emergency download mode firmware path (if any)
  * @bar_num: PCI base address register to use for MHI MMIO register space
  * @dma_data_width: DMA transfer word size (32 or 64 bits)
+ * @sideband_wake: Devices using dedicated sideband GPIO for wakeup instead
+ *		   of inband wake support (such as sdx24)
  */
 struct mhi_pci_dev_info {
 	const struct mhi_controller_config *config;
@@ -40,6 +42,7 @@ struct mhi_pci_dev_info {
 	const char *edl;
 	unsigned int bar_num;
 	unsigned int dma_data_width;
+	bool sideband_wake;
 };
 
 #define MHI_CHANNEL_CONFIG_UL(ch_num, ch_name, el_count, ev_ring) \
@@ -242,7 +245,8 @@ static const struct mhi_pci_dev_info mhi_qcom_sdx65_info = {
 	.edl = "qcom/sdx65m/edl.mbn",
 	.config = &modem_qcom_v1_mhiv_config,
 	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
-	.dma_data_width = 32
+	.dma_data_width = 32,
+	.sideband_wake = false,
 };
 
 static const struct mhi_pci_dev_info mhi_qcom_sdx55_info = {
@@ -251,7 +255,8 @@ static const struct mhi_pci_dev_info mhi_qcom_sdx55_info = {
 	.edl = "qcom/sdx55m/edl.mbn",
 	.config = &modem_qcom_v1_mhiv_config,
 	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
-	.dma_data_width = 32
+	.dma_data_width = 32,
+	.sideband_wake = false,
 };
 
 static const struct mhi_pci_dev_info mhi_qcom_sdx24_info = {
@@ -259,7 +264,8 @@ static const struct mhi_pci_dev_info mhi_qcom_sdx24_info = {
 	.edl = "qcom/prog_firehose_sdx24.mbn",
 	.config = &modem_qcom_v1_mhiv_config,
 	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
-	.dma_data_width = 32
+	.dma_data_width = 32,
+	.sideband_wake = true,
 };
 
 static const struct mhi_channel_config mhi_quectel_em1xx_channels[] = {
@@ -301,7 +307,8 @@ static const struct mhi_pci_dev_info mhi_quectel_em1xx_info = {
 	.edl = "qcom/prog_firehose_sdx24.mbn",
 	.config = &modem_quectel_em1xx_config,
 	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
-	.dma_data_width = 32
+	.dma_data_width = 32,
+	.sideband_wake = true,
 };
 
 static const struct mhi_channel_config mhi_foxconn_sdx55_channels[] = {
@@ -339,7 +346,8 @@ static const struct mhi_pci_dev_info mhi_foxconn_sdx55_info = {
 	.edl = "qcom/sdx55m/edl.mbn",
 	.config = &modem_foxconn_sdx55_config,
 	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
-	.dma_data_width = 32
+	.dma_data_width = 32,
+	.sideband_wake = false,
 };
 
 static const struct pci_device_id mhi_pci_id_table[] = {
@@ -640,9 +648,12 @@ static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	mhi_cntrl->status_cb = mhi_pci_status_cb;
 	mhi_cntrl->runtime_get = mhi_pci_runtime_get;
 	mhi_cntrl->runtime_put = mhi_pci_runtime_put;
-	mhi_cntrl->wake_get = mhi_pci_wake_get_nop;
-	mhi_cntrl->wake_put = mhi_pci_wake_put_nop;
-	mhi_cntrl->wake_toggle = mhi_pci_wake_toggle_nop;
+
+	if (info->sideband_wake) {
+		mhi_cntrl->wake_get = mhi_pci_wake_get_nop;
+		mhi_cntrl->wake_put = mhi_pci_wake_put_nop;
+		mhi_cntrl->wake_toggle = mhi_pci_wake_toggle_nop;
+	}
 
 	err = mhi_pci_claim(mhi_cntrl, info->bar_num, DMA_BIT_MASK(info->dma_data_width));
 	if (err)