usb: dwc3: dwc3-msm-core: Add DIAG IMEM management into DWC3 MSM

Originally, the PID IMEM field was updated as part of the f_diag driver
instance.  Since the f_diag, driver has been removed, relocate this logic
into DWC3 MSM.  Once receiving the pullup enable call, the logic will look
up for the diag function, and if present handle writing the PID and device
serial number to IMEM.  This removes the need for having userspace
update/trigger the IMEM update.

Change-Id: If6ba232270269001690b3cedd3d0de9bf2d4cebb
Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com>

drivers/usb/dwc3/dwc3-msm-core.c

@@ -24,6 +24,7 @@
 #include <linux/of.h>
 #include <linux/of_platform.h>
 #include <linux/of_gpio.h>
+#include <linux/of_address.h>
 #include <linux/list.h>
 #include <linux/uaccess.h>
 #include <linux/usb/ch9.h>
@@ -44,6 +45,7 @@
 #include <linux/usb/dwc3-msm.h>
 #include <linux/usb/role.h>
 #include <linux/usb/redriver.h>
+#include <linux/usb/composite.h>
 
 #include "core.h"
 #include "gadget.h"
@@ -53,6 +55,11 @@
 
 #define NUM_LOG_PAGES   12
 
+/* dload specific suppot */
+#define PID_MAGIC_ID		0x71432909
+#define SERIAL_NUM_MAGIC_ID	0x61945374
+#define SERIAL_NUMBER_LENGTH	128
+
 /* time out to wait for USB cable status notification (in ms)*/
 #define SM_INIT_TIMEOUT 30000
 
@@ -291,6 +298,13 @@ enum usb_gsi_reg {
 	GSI_REG_MAX,
 };
 
+struct dload_struct {
+	u32	pid;
+	char	serial_number[SERIAL_NUMBER_LENGTH];
+	u32	pid_magic;
+	u32	serial_magic;
+};
+
 struct dwc3_hw_ep {
 	struct dwc3_ep		*dep;
 	enum usb_hw_ep_mode	mode;
@@ -590,6 +604,8 @@ struct dwc3_msm {
 /* unfortunately, dwc3 core doesn't manage multiple dwc3 instances for trace */
 void *dwc_trace_ipc_log_ctxt;
 
+static struct dload_struct __iomem *diag_dload;
+
 static void dwc3_pwr_event_handler(struct dwc3_msm *mdwc);
 
 static inline void dwc3_msm_ep_writel(void __iomem *base, u32 offset, u32 value)
@@ -3127,6 +3143,67 @@ static void dwc3_msm_set_clk_sel(struct dwc3_msm *mdwc)
 		dwc3_msm_switch_utmi(mdwc, 1);
 }
 
+static void *gadget_get_drvdata(struct usb_gadget *g)
+{
+	return g->ep0->driver_data;
+}
+
+static int is_diag_enabled(struct usb_composite_dev *cdev)
+{
+	struct usb_configuration	*c;
+
+	list_for_each_entry(c, &cdev->configs, list) {
+		struct usb_function *f;
+
+		f = c->interface[0];
+		if (!strcmp(f->fi->group.cg_item.ci_name, "ffs.diag"))
+			return 1;
+	}
+
+	return 0;
+}
+
+static void dwc3_msm_update_imem_pid(struct dwc3 *dwc)
+{
+	struct usb_composite_dev	*cdev = NULL;
+	struct dload_struct		local_diag_dload = { 0 };
+
+	if (!diag_dload || !dwc->gadget) {
+		pr_err("%s: diag_dload mem region not defined\n", __func__);
+		return;
+	}
+
+	cdev = gadget_get_drvdata(dwc->gadget);
+
+	if (cdev->desc.idVendor == 0x05c6 && is_diag_enabled(cdev)) {
+		struct usb_gadget_string_container *uc;
+		struct usb_string *s;
+
+		local_diag_dload.pid = cdev->desc.idProduct;
+		local_diag_dload.pid_magic = PID_MAGIC_ID;
+		local_diag_dload.serial_magic = SERIAL_NUM_MAGIC_ID;
+
+		list_for_each_entry(uc, &cdev->gstrings, list) {
+			struct usb_gadget_strings **table;
+
+			table = (struct usb_gadget_strings **)uc->stash;
+			if (!table) {
+				pr_err("%s: can't update dload cookie\n", __func__);
+				return;
+			}
+
+			for (s = (*table)->strings; s && s->s; s++) {
+				if (s->id == cdev->desc.iSerialNumber) {
+					strscpy(local_diag_dload.serial_number, s->s,
+						SERIAL_NUMBER_LENGTH);
+					break;
+				}
+			}
+		}
+		memcpy_toio(diag_dload, &local_diag_dload, sizeof(local_diag_dload));
+	}
+}
+
 void dwc3_msm_notify_event(struct dwc3 *dwc,
 		enum dwc3_notify_event event, unsigned int value)
 {
@@ -3283,6 +3360,9 @@ void dwc3_msm_notify_event(struct dwc3 *dwc,
 				GSI_EN_MASK, 0);
 		}
 		break;
+	case DWC3_IMEM_UPDATE_PID:
+		dwc3_msm_update_imem_pid(dwc);
+		break;
 	default:
 		dev_dbg(mdwc->dev, "unknown dwc3 event\n");
 		break;
@@ -5321,6 +5401,7 @@ static int dwc3_msm_parse_core_params(struct dwc3_msm *mdwc, struct device_node
 
 static int dwc3_msm_parse_params(struct dwc3_msm *mdwc, struct device_node *node)
 {
+	struct device_node *diag_node;
 	struct device	*dev = mdwc->dev;
 	int ret, size = 0, i;
 
@@ -5385,6 +5466,12 @@ static int dwc3_msm_parse_params(struct dwc3_msm *mdwc, struct device_node *node
 
 	mdwc->force_gen1 = of_property_read_bool(node, "qcom,force-gen1");
 
+	diag_node = of_find_compatible_node(NULL, NULL, "qcom,msm-imem-diag-dload");
+	if (!diag_node)
+		pr_warn("diag: failed to find diag_dload imem node\n");
+
+	diag_dload  = diag_node ? of_iomap(diag_node, 0) : NULL;
+
 	return 0;
 }
 
@@ -5690,6 +5777,8 @@ static int dwc3_msm_remove(struct platform_device *pdev)
 	struct dwc3 *dwc = platform_get_drvdata(mdwc->dwc3);
 	int i, ret_pm;
 
+	if (diag_dload)
+		iounmap(diag_dload);
 	usb_role_switch_unregister(mdwc->role_switch);
 
 	if (mdwc->dpdm_nb.notifier_call) {

drivers/usb/dwc3/dwc3-msm-ops.c

@@ -112,6 +112,10 @@ static int entry_dwc3_gadget_pullup(struct kretprobe_instance *ri,
 	dwc3_msm_notify_event(data->dwc, DWC3_CONTROLLER_PULLUP_ENTER,
 				data->xi0);
 
+	/* Only write PID to IMEM if pullup is being enabled */
+	if (data->xi0)
+		dwc3_msm_notify_event(data->dwc, DWC3_IMEM_UPDATE_PID, 0);
+
 	return 0;
 }
 

include/linux/usb/dwc3-msm.h

@@ -85,6 +85,7 @@ enum dwc3_notify_event {
 	DWC3_GSI_EVT_BUF_CLEAR,
 	DWC3_GSI_EVT_BUF_FREE,
 	DWC3_CONTROLLER_NOTIFY_CLEAR_DB,
+	DWC3_IMEM_UPDATE_PID,
 };
 
 /*