Re: [PATCH 6/6] mmc: sdhci: fix null return check of regulator_get

[Chris Ball <cjb@laptop.org>]

Hi,

On Tue, Sep 18 2012, Kevin Liu wrote:
> From: Kevin Liu <kliu5@marvell.com>
>
> regulator_get() returns NULL when CONFIG_REGULATOR not defined,
> which should be checked.
>
> Signed-off-by: Bin Wang <binw@marvell.com>
> Signed-off-by: Kevin Liu <kliu5@marvell.com>
> ---
>  drivers/mmc/host/sdhci.c |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 4b5631e..914147d 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -2845,7 +2845,7 @@ int sdhci_add_host(struct sdhci_host *host)
>  
>  	/* If vqmmc regulator and no 1.8V signalling, then there's no UHS */
>  	host->vqmmc = regulator_get(mmc_dev(mmc), "vqmmc");
> -	if (IS_ERR(host->vqmmc)) {
> +	if (IS_ERR_OR_NULL(host->vqmmc)) {
>  		pr_info("%s: no vqmmc regulator found\n", mmc_hostname(mmc));
>  		host->vqmmc = NULL;
>  	}
> @@ -2912,7 +2912,7 @@ int sdhci_add_host(struct sdhci_host *host)
>  	ocr_avail = 0;
>  
>  	host->vmmc = regulator_get(mmc_dev(mmc), "vmmc");
> -	if (IS_ERR(host->vmmc)) {
> +	if (IS_ERR_OR_NULL(host->vmmc)) {
>  		pr_info("%s: no vmmc regulator found\n", mmc_hostname(mmc));
>  		host->vmmc = NULL;
>  	} else

Why should it be checked?  It looks like the only difference will be
that everyone gets the printk, which isn't desirable -- x86 laptop
users don't need to see a scary message about regulators.

Thanks,

- Chris.
-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child