irqchip/renesas-intc-irqpin: Improve clock error handling and reporting

If the Renesas External IRQ Pin driver cannot find a functional clock,
it prints a warning, .e.g.

    renesas_intc_irqpin fe78001c.interrupt-controller: unable to get clock

and continues, as the clock is optional, depending on the SoC type.
This warning may confuse users.

To fix this, add a flag to indicate that the clock is mandatory or
optional, and add a few more compatible entries:
  - If the clock is mandatory (on R-Mobile A1 or SH-Mobile AG5), a
    missing clock is now treated as a fatal error,
  - If the clock is optional (on R-Car Gen1, or using the generic
    "renesas,intc-irqpin" compatible value), the warning is no longer
    printed.

This requires making struct intc_irqpin_irlm_config more generic by
renaming it to intc_irqpin_config, and adding a flag to indicate if IRLM
is needed.
The new clock flag is merged with the existing shared_irqs boolean into
a bitfield to save space.

Suggested-by: Magnus Damm <magnus.damm@gmail.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lkml.kernel.org/r/1448377693-19597-1-git-send-email-geert+renesas@glider.be
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

1 files changed, 33 insertions, 12 deletions

diff --git a/drivers/irqchip/irq-renesas-intc-irqpin.c b/drivers/irqchip/irq-renesas-intc-irqpin.c
index 7f6cf19aa6ac..713177d97c7a 100644
--- a/drivers/irqchip/irq-renesas-intc-irqpin.c
+++ b/drivers/irqchip/irq-renesas-intc-irqpin.c
@@ -79,12 +79,15 @@ struct intc_irqpin_priv {
         struct irq_chip irq_chip;
         struct irq_domain *irq_domain;
         struct clk *clk;
-        bool shared_irqs;
+        unsigned shared_irqs:1;
+        unsigned needs_clk:1;
         u8 shared_irq_mask;
 };
 
-struct intc_irqpin_irlm_config {
+struct intc_irqpin_config {
         unsigned int irlm_bit;
+        unsigned needs_irlm:1;
+        unsigned needs_clk:1;
 };
 
 static unsigned long intc_irqpin_read32(void __iomem *iomem)
@@ -359,8 +362,15 @@ static const struct irq_domain_ops intc_irqpin_irq_domain_ops = {
         .xlate  = irq_domain_xlate_twocell,
 };
 
-static const struct intc_irqpin_irlm_config intc_irqpin_irlm_r8a777x = {
+static const struct intc_irqpin_config intc_irqpin_irlm_r8a777x = {
         .irlm_bit = 23, /* ICR0.IRLM0 */
+        .needs_irlm = 1,
+        .needs_clk = 0,
+};
+
+static const struct intc_irqpin_config intc_irqpin_rmobile = {
+        .needs_irlm = 0,
+        .needs_clk = 1,
 };
 
 static const struct of_device_id intc_irqpin_dt_ids[] = {
@@ -369,12 +379,17 @@ static const struct of_device_id intc_irqpin_dt_ids[] = {
           .data = &intc_irqpin_irlm_r8a777x },
         { .compatible = "renesas,intc-irqpin-r8a7779",
           .data = &intc_irqpin_irlm_r8a777x },
+        { .compatible = "renesas,intc-irqpin-r8a7740",
+          .data = &intc_irqpin_rmobile },
+        { .compatible = "renesas,intc-irqpin-sh73a0",
+          .data = &intc_irqpin_rmobile },
         {},
 };
 MODULE_DEVICE_TABLE(of, intc_irqpin_dt_ids);
 
 static int intc_irqpin_probe(struct platform_device *pdev)
 {
+        const struct intc_irqpin_config *config = NULL;
         struct device *dev = &pdev->dev;
         const struct of_device_id *of_id;
         struct intc_irqpin_priv *p;
@@ -407,9 +422,19 @@ static int intc_irqpin_probe(struct platform_device *pdev)
         p->pdev = pdev;
         platform_set_drvdata(pdev, p);
 
+        of_id = of_match_device(intc_irqpin_dt_ids, dev);
+        if (of_id && of_id->data) {
+                config = of_id->data;
+                p->needs_clk = config->needs_clk;
+        }
+
         p->clk = devm_clk_get(dev, NULL);
         if (IS_ERR(p->clk)) {
-                dev_warn(dev, "unable to get clock\n");
+                if (p->needs_clk) {
+                        dev_err(dev, "unable to get clock\n");
+                        ret = PTR_ERR(p->clk);
+                        goto err0;
+                }
                 p->clk = NULL;
         }
 
@@ -479,14 +504,10 @@ static int intc_irqpin_probe(struct platform_device *pdev)
         }
 
         /* configure "individual IRQ mode" where needed */
-        of_id = of_match_device(intc_irqpin_dt_ids, dev);
-        if (of_id && of_id->data) {
-                const struct intc_irqpin_irlm_config *irlm_config = of_id->data;
-
+        if (config && config->needs_irlm) {
                 if (io[INTC_IRQPIN_REG_IRLM])
                         intc_irqpin_read_modify_write(p, INTC_IRQPIN_REG_IRLM,
-                                                      irlm_config->irlm_bit,
-                                                      1, 1);
+                                                      config->irlm_bit, 1, 1);
                 else
                         dev_warn(dev, "unable to select IRLM mode\n");
         }
@@ -500,10 +521,10 @@ static int intc_irqpin_probe(struct platform_device *pdev)
 
         /* scan for shared interrupt lines */
         ref_irq = p->irq[0].requested_irq;
-        p->shared_irqs = true;
+        p->shared_irqs = 1;
         for (k = 1; k < nirqs; k++) {
                 if (ref_irq != p->irq[k].requested_irq) {
-                        p->shared_irqs = false;
+                        p->shared_irqs = 0;
                         break;
                 }
         }