On Wed, Nov 13, 2013 at 08:40:54AM +0100, Krzysztof Kozlowski wrote:
> +/**
> + * After resuming from suspend it may happen that IRQ is signalled but
> + * IRQ GPIO is not high. Also the interrupt registers won't have any data
> + * (all of them equal to 0x00).
> + *
> + * In such case retry few times reading the interrupt registers.
> + */
> +#define IRQ_READ_REG_RETRY_CNT 5
What is the cause here? This smells like an unreliable workaround for
some other behaviour. In general this all looks very like standard
regmap code.
> + for (i = 0; i < MAX14577_IRQ_REGS_NUM; i++) {
> + u8 mask_reg = max14577_mask_reg[i];
> +
> + if (mask_reg == MAX14577_REG_INVALID ||
> + IS_ERR_OR_NULL(max14577->regmap))
> + continue;
Why would this code even be running if you don't have a register map?
> + dev_info(max14577->dev, "Got interrupts [1:0x%02x, 2:0x%02x, 3:0x%02x]\n",
> + irq_reg[MAX14577_IRQ_INT1], irq_reg[MAX14577_IRQ_INT2],
> + irq_reg[MAX14577_IRQ_INT3]);
This is far too noisy, dev_dbg() at most.
> + gpio_val = gpio_get_value(pdata->irq_gpio);
> +
> + if (gpio_get_value(pdata->irq_gpio) == 0)
> + dev_warn(max14577->dev, "IRQ GPIO is not high, retry reading interrupt registers\n");
> + } while (gpio_val == 0 && --retry > 0);
This looks very strange...
> + max14577->irq = gpio_to_irq(pdata->irq_gpio);
> + ret = gpio_request(pdata->irq_gpio, "max14577_irq");
> + if (ret) {
> + dev_err(max14577->dev, "Failed requesting GPIO %d: %d\n",
> + pdata->irq_gpio, ret);
> + goto err;
> + }
> + gpio_direction_input(pdata->irq_gpio);
> + gpio_free(pdata->irq_gpio);
This means the GPIO handling code that was present in the handling is
broken, it's trying to use the GPIO after it was freed.
> + ret = request_threaded_irq(max14577->irq, NULL, max14577_irq_thread,
> + IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
> + "max14577-irq", max14577);
Are you *positive* this is a falling triggered IRQ? All the code to do
with spinning reading the GPIO state during handling makes it look like
this is in fact an active low interrupt and a lot of the code in here is
working around trying to handle that as the wrong kind of IRQ.
> +int max14577_bulk_write(struct regmap *map, u8 reg, u8 *buf, int count)
> +{
> + return regmap_bulk_write(map, reg, buf, count);
> +}
> +EXPORT_SYMBOL_GPL(max14577_bulk_write);
Given that these are basically all trivial wrappers around regmap they
probably ought to be static inlines in the header.
> +static struct max14577_platform_data *max14577_i2c_parse_dt(struct device *dev)
> +{
There's no DT binding document?
> +const struct dev_pm_ops max14577_pm = {
> + .suspend = max14577_suspend,
> + .resume = max14577_resume,
> +};
SET_SYSTEM_SLEEP_PM_OPS().
> +static int __init max14577_i2c_init(void)
> +{
> + return i2c_add_driver(&max14577_i2c_driver);
> +}
> +subsys_initcall(max14577_i2c_init);
Why not module_i2c_driver?
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