Audio: Configure SSP3 for CTP in Audio driver

BZ: 25850

In Medfield, SSPx is configured by SCU FW. However, in CTP platform
it is not done.

The solution can be:-
CASE1:
If audio driver should not be involved in SSP3 ALT-FUNC config then
it has be to be done as follows:
- In IFWI UMIP header, configure the GPIO pins, so that IA FW sets the
corresponding FLIS registers.
- During Audio D0i3 entry/exit, SCU FW saves and restores these values.

CASE2:
- audio driver configures SSP3 ALT-FUNC in probe.
- During Audio D0i3 entry/exit, SCU FW saves and restores these values.

CASE3:
- audio driver configures SSP3 ALT_FUNC in probe and resume.

As a workaround solution for usecase integration, CASE3 is implemented.
If there is a power impact then we need to go for CASE1 or CASE2.

Change-Id: I13f92b9559f4efe27feb9bec926ddc88946e0e60
Signed-off-by: Vaibhav Agarwal <vaibhav.agarwal@intel.com>
Reviewed-on: http://android.intel.com:8080/37685
Reviewed-by: buildbot <buildbot@intel.com>
Reviewed-by: Abdullah, Omair M <omair.m.abdullah@intel.com>
Reviewed-by: Babu, Ramesh <ramesh.babu@intel.com>
Reviewed-by: Kp, Jeeja <jeeja.kp@intel.com>
Reviewed-by: Koul, Vinod <vinod.koul@intel.com>
Reviewed-by: Gupta, ArvindX K <arvindx.k.gupta@intel.com>
Reviewed-by: M, Arulselvan <arulselvan.m@intel.com>
Tested-by: M, Arulselvan <arulselvan.m@intel.com>

diff --git a/sound/pci/Kconfig b/sound/pci/Kconfig
index f13f51a..700be8d 100644 (file)
--- a/sound/pci/Kconfig
+++ b/sound/pci/Kconfig
@@ -11,7 +11,7 @@ if SND_PCI
 
 config SND_INTEL_SST
        tristate "Intel SST (LPE) Driver"
-       depends on X86 && INTEL_SCU_IPC
+       depends on X86 && INTEL_SCU_IPC && GPIO_LANGWELL
        default n
        help
          Say Y here to include support for the Intel(R) MID SST DSP driver

diff --git a/sound/pci/sst/intel_sst.c b/sound/pci/sst/intel_sst.c
index c616e0b..de97691 100644 (file)
--- a/sound/pci/sst/intel_sst.c
+++ b/sound/pci/sst/intel_sst.c
@@ -38,6 +38,7 @@
 #include <linux/miscdevice.h>
 #include <linux/pm_runtime.h>
 #include <linux/async.h>
+#include <linux/lnw_gpio.h>
 #include <asm/intel-mid.h>
 #include <asm/intel_scu_ipc.h>
 #include <sound/intel_sst.h>
@@ -54,6 +55,12 @@ MODULE_DESCRIPTION("Intel (R) SST(R) Audio Engine Driver");
 MODULE_LICENSE("GPL v2");
 MODULE_VERSION(SST_DRIVER_VERSION);
 
+/* GPIO pins used for SSP3 */
+#define CLV_I2S_3_CLK_GPIO_PIN 12
+#define CLV_I2S_3_FS_GPIO_PIN  13
+#define CLV_I2S_3_TXD_GPIO_PIN 74
+#define CLV_I2S_3_RXD_GPIO_PIN 75
+
 struct intel_sst_drv *sst_drv_ctx;
 static struct mutex drv_ctx_lock;
 struct class *sst_class;
@@ -364,6 +371,17 @@ static int __devinit intel_sst_probe(struct pci_dev *pci,
                csr2 |= BIT(1)|BIT(2);
                sst_shim_write(sst_drv_ctx->shim, SST_CSR2, csr2);
        }
+
+       /* GPIO_PIN 12,13,74,75 needs to be configured in
+        * ALT_FUNC_2 mode for SSP3 IOs
+        */
+       if (sst_drv_ctx->pci_id == SST_CLV_PCI_ID) {
+               lnw_gpio_set_alt(CLV_I2S_3_CLK_GPIO_PIN, LNW_ALT_2);
+               lnw_gpio_set_alt(CLV_I2S_3_FS_GPIO_PIN, LNW_ALT_2);
+               lnw_gpio_set_alt(CLV_I2S_3_TXD_GPIO_PIN, LNW_ALT_2);
+               lnw_gpio_set_alt(CLV_I2S_3_RXD_GPIO_PIN, LNW_ALT_2);
+       }
+
        sst_drv_ctx->lpe_stalled = 0;
        pci_set_drvdata(pci, sst_drv_ctx);
        pm_runtime_allow(&pci->dev);
@@ -584,6 +602,16 @@ static int intel_sst_runtime_resume(struct device *dev)
        csr |= (sst_drv_ctx->csr_value | 0x30000);
        sst_shim_write(sst_drv_ctx->shim, SST_CSR, csr);
 
+       /* GPIO_PIN 12,13,74,75 needs to be configured in
+        * ALT_FUNC_2 mode for SSP3 IOs
+        */
+       if (sst_drv_ctx->pci_id == SST_CLV_PCI_ID) {
+               lnw_gpio_set_alt(CLV_I2S_3_CLK_GPIO_PIN, LNW_ALT_2);
+               lnw_gpio_set_alt(CLV_I2S_3_FS_GPIO_PIN, LNW_ALT_2);
+               lnw_gpio_set_alt(CLV_I2S_3_TXD_GPIO_PIN, LNW_ALT_2);
+               lnw_gpio_set_alt(CLV_I2S_3_RXD_GPIO_PIN, LNW_ALT_2);
+       }
+
        intel_sst_set_pll(true, SST_PLL_AUDIO);
        sst_set_fw_state_locked(sst_drv_ctx, SST_UN_INIT);
        return 0;