[PATCH 8/9 v2] MXC: Add a digital audio multiplexer driver

[javier Martin]

Hi Sascha,
as you know I have been testing your i.MX27 support and I have found a
problem in this audmux patch.

Please, see my comment below:


+++ b/arch/arm/plat-mxc/audmux-v1.c
> @@ -0,0 +1,53 @@
> +/*
> + * Copyright 2009 Pengutronix, Sascha Hauer <s.hauer at pengutronix.de>
> + *
> + * Initial development of this code was funded by
> + * Phytec Messtechnik GmbH, http://www.phytec.de
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/err.h>
> +#include <linux/io.h>
> +#include <linux/clk.h>
> +#include <mach/audmux.h>
> +#include <mach/hardware.h>
> +
> +static void __iomem *audmux_base;
> +
> +#define MXC_AUDMUX_V1_PCR(x)   ((x) * 4)
>

You cannot calculate AUDMUX register offsets this way because according to
i.MX27 manual:

0x1001_6000 (HPCR1)
0x1001_6004 (HPCR2)
0x1001_6008 (HPCR3)
0x1001_6010 (PPCR1)  <-- You are using 0x0C for this
0x1001_6014 (PPCR2)  <--- You are using 0x10 for this
0x1001_601C (PPCR3)  <--- You are using 0x18 for this


+int mxc_audmux_v1_configure_port(unsigned int port, unsigned int pcr)
> +{
> +       if (!audmux_base) {
> +               printk("%s: not configured\n", __func__);
> +               return -ENOSYS;
> +       }
> +
> +       writel(pcr, audmux_base + MXC_AUDMUX_V1_PCR(port));
> +
> +       return 0;
> +}
> +EXPORT_SYMBOL_GPL(mxc_audmux_v1_configure_port);
> +
> +static int mxc_audmux_v1_init(void)
> +{
> +       if (cpu_is_mx27() || cpu_is_mx21())
> +               audmux_base = IO_ADDRESS(AUDMUX_BASE_ADDR);
> +       return 0;
> +}
> +
> +postcore_initcall(mxc_audmux_v1_init);
>
>

Thank you.

-- 
Javier Martin
Vista Silicon S.L.
CDTUC - FASE C - Oficina S-345
Avda de los Castros s/n
39005- Santander. Cantabria. Spain
+34 942 25 32 60
www.vista-silicon.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20091130/7a393e51/attachment-0001.htm>