drivers: staging: gte_test: Unwind and other issues

There are bugs in test driver as follows:
1) gpio unwind is not done during init
2) No guard against re-registering event, for example, if user issues
echo 1 > gpio_en_dis, it will overwrite existing event descriptor

Also, it has other issues as below:
1) print debug messages correction in init
2) No print messages when timestamp is not available
3) Kconfig has extra blank lines

This CL addresses all above issue.

Bug 2865212

Change-Id: I66f4bd377c4d3557b46ab5828dabad4ee8394454
Signed-off-by: Dipen Patel <dipenp@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nvidia/+/2302019
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Winnie Hsu <whsu@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>
GVS: Gerrit_Virtual_Submit

2 files changed, 64 insertions, 15 deletions

diff --git a/drivers/staging/platform/tegra/gte_test/Kconfig b/drivers/staging/platform/tegra/gte_test/Kconfig
index 7b4fbf1d2..5130e1638 100644
--- a/drivers/staging/platform/tegra/gte_test/Kconfig
+++ b/drivers/staging/platform/tegra/gte_test/Kconfig
@@ -4,5 +4,4 @@ config TEGRA_GTE_TEST
         help
           Enable this option for integrated generic timestamping support on
           NVIDIA Tegra systems-on-chip. The driver supports LIC IRQs and AON
-          GPIO monitoring for hardware timestamping.
-
+          GPIO monitoring for hardware timestamping.
\ No newline at end of file
diff --git a/drivers/staging/platform/tegra/gte_test/tegra194_gte_test.c b/drivers/staging/platform/tegra/gte_test/tegra194_gte_test.c
index bea0df14c..2311aa143 100644
--- a/drivers/staging/platform/tegra/gte_test/tegra194_gte_test.c
+++ b/drivers/staging/platform/tegra/gte_test/tegra194_gte_test.c
@@ -83,17 +83,34 @@ static ssize_t store_gpio_en_dis(struct kobject *kobj,
         }
 
         if (val == 1) {
+                if (gte.data_gpio) {
+                        pr_info("gpio_in is already registered\n");
+                        ret = -EEXIST;
+                        goto error;
+                }
                 gte.data_gpio = tegra_gte_register_event(np, gpio_in);
                 if (IS_ERR(gte.data_gpio)) {
                         pr_err("Could not register gpio\n");
-                        ret = -EINVAL;
+                        ret = PTR_ERR(gte.data_gpio);
+                        gte.data_gpio = NULL;
                         goto error;
                 }
         } else if (val == 0) {
-                if (tegra_gte_unregister_event(gte.data_gpio) != 0) {
+                if (!gte.data_gpio) {
+                        pr_info("gpio_in is not registered\n");
                         ret = -EINVAL;
                         goto error;
                 }
+                ret = tegra_gte_unregister_event(gte.data_gpio);
+                if (ret == -EBUSY) {
+                        /* User should retry */
+                        pr_err("failed to unregister gpio in\n");
+                        goto error;
+                } else { /* For anything else set data to null */
+                        gte.data_gpio = NULL;
+                        if (ret == 0)
+                                ret = count;
+                }
         } else {
                 ret = -EINVAL;
         }
@@ -126,17 +143,34 @@ static ssize_t store_lic_irq_en_dis(struct kobject *kobj,
         }
 
         if (val == 1) {
+                if (gte.data_lic) {
+                        pr_info("lic_irq is already registered\n");
+                        ret = -EEXIST;
+                        goto error;
+                }
                 gte.data_lic = tegra_gte_register_event(np, lic_irq);
                 if (IS_ERR(gte.data_lic)) {
                         pr_err("Could not register lic irq\n");
-                        ret = -EINVAL;
+                        ret = PTR_ERR(gte.data_lic);
+                        gte.data_lic = NULL;
                         goto error;
                 }
         } else if (val == 0) {
-                if (tegra_gte_unregister_event(gte.data_lic) != 0) {
+                if (!gte.data_lic) {
+                        pr_info("lic_irq is not registered\n");
                         ret = -EINVAL;
                         goto error;
                 }
+                ret = tegra_gte_unregister_event(gte.data_lic);
+                if (ret == -EBUSY) {
+                        /* User should retry */
+                        pr_err("failed to unregister lic irq\n");
+                        goto error;
+                } else { /* For anything else set data to null */
+                        gte.data_lic = NULL;
+                        if (ret == 0)
+                                ret = count;
+                }
         } else {
                 ret = -EINVAL;
         }
@@ -206,8 +240,10 @@ static irqreturn_t tegra_gte_test_gpio_isr(int irq, void *data)
         struct tegra_gte_ev_detail hts;
         struct tegra_gte_test *gte = data;
 
-        if (tegra_gte_retrieve_event((gte->data_gpio), &hts) != 0)
+        if (tegra_gte_retrieve_event((gte->data_gpio), &hts) != 0) {
+                pr_info("No timestamp available\n");
                 return IRQ_HANDLED;
+        }
 
         pr_info("GPIO HW Timestamp: raw %llu, ns %llu\n",
                  hts.ts_raw, hts.ts_ns);
@@ -219,10 +255,13 @@ static int __init tegra_gte_test_init(void)
         int ret = 0;
 
         if (gpio_out == -EINVAL || gpio_in == -EINVAL || lic_irq == EINVAL) {
-                pr_err("Invalid gpio_out, gpio_in, gpiochip_base and irq\n");
+                pr_err("Invalid gpio_out, gpio_in and irq\n");
                 return -EINVAL;
         }
 
+        gte.data_lic = NULL;
+        gte.data_gpio = NULL;
+
         ret = gpio_request(gpio_out, "gte_test_gpio_out");
         if (ret) {
                 pr_err("failed request gpio out\n");
@@ -232,26 +271,31 @@ static int __init tegra_gte_test_init(void)
         ret = gpio_direction_output(gpio_out, 0);
         if (ret) {
                 pr_err("failed to set pin direction\n");
-                return -EINVAL;
+                ret = -EINVAL;
+                goto free_gpio_out;
         }
 
         ret = gpio_request(gpio_in, "gte_test_gpio_in");
         if (ret) {
                 pr_err("failed to request gpio in\n");
-                return -EINVAL;
+                ret = -EINVAL;
+                goto free_gpio_out;
         }
 
         ret = gpio_direction_input(gpio_in);
         if (ret) {
                 pr_err("failed to set pin direction\n");
-                return -EINVAL;
+                ret = -EINVAL;
+                goto free_gpio_in;
+
         }
 
         /* IRQ setup */
         ret = gpio_to_irq(gpio_in);
         if (ret < 0) {
                 pr_err("failed to map GPIO to IRQ: %d\n", ret);
-                return -EINVAL;
+                ret = -EINVAL;
+                goto free_gpio_in;
         }
 
         gte.gpio_in_irq = ret;
@@ -261,14 +305,15 @@ static int __init tegra_gte_test_init(void)
                          "tegra_gte_test_isr", &gte);
         if (ret) {
                 pr_err("failed to acquire IRQ\n");
-                return ret;
+                ret = -EINVAL;
+                goto free_gpio_in;
         }
 
         ret = tegra_gte_test_sysfs_create();
         if (ret != 0) {
                 pr_err("sysfs creation failed\n");
                 ret = -EINVAL;
-                goto error;
+                goto free_irq;
         }
 
         setup_timer(&gte.timer, gpio_timer_cb, 0);
@@ -276,8 +321,13 @@ static int __init tegra_gte_test_init(void)
 
         return 0;
 
-error:
+free_irq:
         free_irq(gte.gpio_in_irq, &gte);
+free_gpio_in:
+        gpio_free(gpio_in);
+free_gpio_out:
+        gpio_free(gpio_out);
+
         return ret;
 }