Subject: [PATCH v3 05/10] spmi: pmic_arb: add support for interrupt handling

From: [email-masked] (Stephen Boyd)
Date: Wed, 30 Oct 2013 11:17:55 -0700

On 10/28, Josh Cartwright wrote:
> @@ -108,12 +111,17 @@ struct spmi_pmic_arb_dev {
>  	void __iomem		*base;
>  	void __iomem		*intr;
>  	void __iomem		*cnfg;
> +	unsigned int		irq;
>  	bool			allow_wakeup;
>  	spinlock_t		lock;
>  	u8			channel;
>  	u8			min_apid;
>  	u8			max_apid;
>  	u32			mapping_table[SPMI_MAPPING_TABLE_LEN];
> +	int			bus_nr;

This looks unused.

> +	struct irq_domain	*domain;
> +	struct spmi_controller	*spmic;
> +	u16			apid_to_ppid[256];
>  };
>  
>  static inline u32 pmic_arb_base_read(struct spmi_pmic_arb_dev *dev, u32 offset)
[...]
> +
> +static void pmic_arb_chained_irq(unsigned int irq, struct irq_desc *desc)
> +{
> +	struct spmi_pmic_arb_dev *pa = irq_get_handler_data(irq);
> +	struct irq_chip *chip = irq_get_chip(irq);
> +	void __iomem *intr = pa->intr;
> +	int first = pa->min_apid >> 5;
> +	int last = pa->max_apid >> 5;
> +	int i, id;
> +	u8 ee = 0; /*pa->owner;*/

TODO?

> +	u32 status;
> +
> +	chained_irq_enter(chip, desc);
> +
> +	for (i = first; i <= last; ++i) {
> +		status = readl_relaxed(intr + SPMI_PIC_OWNER_ACC_STATUS(ee, i));
> +		while (status) {
> +			id = ffs(status) - 1;
> +			status &= ~(1 << id);
> +			periph_interrupt(pa, id + i * 32);
> +		}
> +	}
> +
> +	chained_irq_exit(chip, desc);
> +}
> +
[...]
> +static int qpnpint_irq_domain_dt_translate(struct irq_domain *d,
> +					   struct device_node *controller,
> +					   const u32 *intspec,
> +					   unsigned int intsize,
> +					   unsigned long *out_hwirq,
> +					   unsigned int *out_type)
> +{
> +	struct spmi_pmic_arb_dev *pa = d->host_data;
> +	struct spmi_pmic_arb_irq_spec spec;
> +	int err;
> +	u8 apid;
> +
> +	dev_dbg(&pa->spmic->dev,
> +		"intspec[0] 0x%1x intspec[1] 0x%02x intspec[2] 0x%02x\n",
> +		intspec[0], intspec[1], intspec[2]);
> +
> +	if (d->of_node != controller)
> +		return -EINVAL;
> +	if (intsize != 4)
> +		return -EINVAL;
> +	if (intspec[0] > 0xF || intspec[1] > 0xFF || intspec[2] > 0x7)
> +		return -EINVAL;
> +
> +	spec.slave = intspec[0];
> +	spec.per   = intspec[1];
> +	spec.irq   = intspec[2];
> +
> +	err = search_mapping_table(pa, &spec, &apid);
> +	if (err)
> +		return err;
> +
> +	pa->apid_to_ppid[apid] = spec.slave << 8 | spec.per;
> +
> +	/* Keep track of {max,min}_apid for bounding search during interrupt */
> +	if (apid > pa->max_apid)
> +		pa->max_apid = apid;
> +	if (apid < pa->min_apid)
> +		pa->min_apid = apid;

Ah makes sense now why we set this to the opposite values in
probe.  Please put a comment in patch 4 and maybe move that setup
in patch 4 to this patch.

> +
> +	*out_hwirq = spec.slave << 24
> +		   | spec.per   << 16
> +		   | spec.irq   << 8
> +		   | apid;
> +	*out_type  = intspec[3] & IRQ_TYPE_SENSE_MASK;
> +
> +	dev_dbg(&pa->spmic->dev, "out_hwirq = %lu\n", *out_hwirq);
> +
> +	return 0;
> +}
> +
[...]
>  static int spmi_pmic_arb_probe(struct platform_device *pdev)
>  {
>  	struct spmi_pmic_arb_dev *pa;
>  	struct spmi_controller *ctrl;
>  	struct resource *res;
> -	int err, i;
> +	int err = 0, i;
>  
>  	ctrl = spmi_controller_alloc(&pdev->dev, sizeof(*pa));
>  	if (!ctrl)
>  		return -ENOMEM;
>  
>  	pa = spmi_controller_get_drvdata(ctrl);
> +	pa->spmic = ctrl;
>  
>  	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "core");
>  	pa->base = devm_ioremap_resource(&ctrl->dev, res);
> @@ -349,6 +679,12 @@ static int spmi_pmic_arb_probe(struct platform_device *pdev)
>  		goto err_put_ctrl;
>  	}
>  
> +	pa->irq = platform_get_irq(pdev, 0);
> +	if (pa->irq < 0) {
> +		err = pa->irq;
> +		goto err_put_ctrl;
> +	}
> +
>  	for (i = 0; i < ARRAY_SIZE(pa->mapping_table); ++i)
>  		pa->mapping_table[i] = readl_relaxed(
>  				pa->cnfg + SPMI_MAPPING_TABLE_REG(i));
> @@ -364,15 +700,30 @@ static int spmi_pmic_arb_probe(struct platform_device *pdev)
>  	ctrl->read_cmd = pmic_arb_read_cmd;
>  	ctrl->write_cmd = pmic_arb_write_cmd;
>  
> +	dev_dbg(&pdev->dev, "adding irq domain\n");
> +	pa->domain = irq_domain_add_tree(pdev->dev.of_node,
> +					 &pmic_arb_irq_domain_ops, pa);
> +	if (!pa->domain) {
> +		dev_err(&pdev->dev, "unable to create irq_domain\n");
> +		goto err_put_ctrl;

Why do we silently ignore the error here? Is the irqchip
functionality optional? Setting err here should allow us to skip
intializing err to 0 up at the top of this function.

> +	}
> +
> +	irq_set_handler_data(pa->irq, pa);
> +	irq_set_chained_handler(pa->irq, pmic_arb_chained_irq);
> +
>  	err = spmi_controller_add(ctrl);
>  	if (err)
> -		goto err_put_ctrl;
> +		goto err_domain_remove;
>  
>  	dev_dbg(&ctrl->dev, "PMIC Arb Version 0x%x\n",
>  		pmic_arb_base_read(pa, PMIC_ARB_VERSION));
>  
>  	return 0;
>  
> +err_domain_remove:
> +	irq_set_chained_handler(pa->irq, NULL);
> +	irq_set_handler_data(pa->irq, NULL);
> +	irq_domain_remove(pa->domain);
>  err_put_ctrl:
>  	spmi_controller_put(ctrl);
>  	return err;

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