Re: [PATCH 2/2] mtd: msm_nand: Add initial msm nand driver support.

From: Murali Nalajala
Date: Fri Apr 15 2011 - 10:50:24 EST

On 4/15/2011 3:21 PM, Artem Bityutskiy wrote:
On Tue, 2011-03-01 at 06:17 +0530, Murali Nalajala wrote:
+#define pr_fmt(fmt) "%s:" fmt, __func__
+#include "msm_nand.h"
+unsigned long msm_nand_phys;

No global variables like this please. Here is how you use them:

+extern unsigned long msm_nand_phys;

extern declaration in the 'C' file causing warning. We are in plan to upload the OneNAND changes soon which makes use of the same .h file.

+#define MSM_NAND_REG(off) (msm_nand_phys + (off))
+#define MSM_NAND_ADDR0 MSM_NAND_REG(0x0004)

Could you please make the macros to take the "struct msm_nand_chip
*chip" argument instead, and store the pase address there. Do not hide
the fact that those macros are actually functions, not constant - this
is error prone.

Besides, I'm do not know your HW, but if you have several controllers
with various base addresses - your driver won't work.

you are correct, we have multiple controllers, which breaks this logic in future.

+ pr_info("Save cfg0 = %x cfg1 = %x\n", chip->cfg0, chip->cfg1);
+ pr_info("cfg0: cw/page=%d ud_sz=%d ecc_sz=%d spare_sz=%d "
+ "num_addr_cycles=%d\n", (chip->cfg0>> 6)& 7,
+ (chip->cfg0>> 9)& 0x3ff, (chip->cfg0>> 19)& 15,
+ (chip->cfg0>> 23)& 15, (chip->cfg0>> 27)& 7);

Please, revise all your pr_info() calls and turn most of them into
dev_dbg() or pr_debug. Your driver should be completely silent by
default, except of error messages and some information messages when it
is initialized.

I will revise all the pr_info calls and change the inappropriate calls to pr_debug.

Murali N

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