Re: [PATCH v3] serial: 8250: add gpio support to exar

Sudip Mukherjee
2015-12-20T14:47:35Z

On Sun, Dec 20, 2015 at 04:18:17PM +0200, Andy Shevchenko wrote:
> On Sun, Dec 20, 2015 at 3:24 PM, Sudip Mukherjee
> <sudipm.mukherjee@gmail.com> wrote:
> > Exar XR17V352/354/358 chips have 16 multi-purpose inputs/outputs which
> > can be controlled using gpio interface.
> > Add support to use these pins and select GPIO_SYSFS also so that these
> > pins can be used from the userspace through sysfs.
> >
> > Tested-by: Rob Groner <rgroner@rtd.com>
> > Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
>
Hi Andy,
Thanks for the review. Just a few doubts below.

> > @@ -0,0 +1,261 @@
> > +/*
> > + * GPIO driver for Exar XR17V35X chip
> > + *
> > + * Copyright (C) 2015 Sudip Mukherjee <sudipm.mukherjee@gmail.com>
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License version 2 as
> > + * published by the Free Software Foundation.
> > + */
<snip>
> > +
> > +err_destroy:
> > + mutex_unlock(&exar_mtx);
> > + mutex_destroy(&exar_gpio->lock);
> > +err_unmap:
> > + iounmap(p);
>
> pci_iounmap?

I thought about pci_iounmap but I saw that most of the code in
8250_pci.c is using iounmap, so i went in favor of the majority.
Will change it.

>
> > + return ret;
> > +}
> > +EXPORT_SYMBOL(xr17v35x_gpio_init);
> > +
>
> > +static void __exit exar_gpio_exit(void)
> > +{
> > +}
> > +
> > +module_exit(exar_gpio_exit);
> > +
> > +static int __init exar_gpio_init(void)
> > +{
> > + return 0;
> > +}
> > +
> > +module_init(exar_gpio_init);
> > +
>
> Useless for now. You are using it as a library.

Main doubt here. If I do not give the module_init() and module_exit()
then what entry do i keep in the Kconfig? In this v3, it is kept as
tristate. Should that be bool then?

regards
sudip