Re: [RESEND PATCH v7 2/2] mmc: OCTEON: Add host driver for OCTEON MMC controller

[Arnd Bergmann <arnd@arndb.de>]

On Thursday 31 March 2016 16:26:53 Matt Redfearn wrote:
> +struct octeon_mmc_host {
> +	u64	base;
> +	u64	ndf_base;
> +	u64	emm_cfg;
> +	u64	n_minus_one;  /* OCTEON II workaround location */
> +	int	last_slot;
> +
> +	struct semaphore mmc_serializer;

Please don't add any new semaphores to the kernel, use a mutex or
a completion instead.

> +#if 0
> +#define octeon_mmc_dbg trace_printk
> +#else
> +static inline void octeon_mmc_dbg(const char *s, ...) { }
> +#endif

Remove this and use dev_dbg() or pr_debug(), it does the same thing.

> +static irqreturn_t octeon_mmc_interrupt(int irq, void *dev_id)

This function is rather long, can you split it up a bit for
readability?

> +{
> +	struct octeon_mmc_host *host = dev_id;
> +	union cvmx_mio_emm_int emm_int;
> +	struct mmc_request	*req;
> +	bool host_done;
> +	union cvmx_mio_emm_rsp_sts rsp_sts;
> +	unsigned long flags = 0;
> +
> +	if (host->need_irq_handler_lock)
> +		spin_lock_irqsave(&host->irq_handler_lock, flags);
> +	else
> +		__acquire(&host->irq_handler_lock);

The locking seems odd, why do you only sometimes have to take the lock,
and why do you disable interrupts from within the irq handler?

	Arnd