mfd: ab8500-debugfs: Formated access AB8500 registers from debugfs entry

Add debugfs entry ab8500/hwreg to read/write bit-field in AB8500 registers.
Check the debugfs entries usage from heading comments in ab8500-debugfs.c

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: carriere etienne <etienne.carriere@stericsson.com>
Reviewed-by: Mattias WALLIN <mattias.wallin@stericsson.com>
This commit is contained in:
carriere etienne 2011-04-08 16:26:36 +02:00 committed by Lee Jones
parent fad55a869b
commit 0fbce76eff
1 changed files with 336 additions and 50 deletions

View File

@ -4,6 +4,72 @@
* Author: Mattias Wallin <mattias.wallin@stericsson.com> for ST-Ericsson.
* License Terms: GNU General Public License v2
*/
/*
* AB8500 register access
* ======================
*
* read:
* # echo BANK > <debugfs>/ab8500/register-bank
* # echo ADDR > <debugfs>/ab8500/register-address
* # cat <debugfs>/ab8500/register-value
*
* write:
* # echo BANK > <debugfs>/ab8500/register-bank
* # echo ADDR > <debugfs>/ab8500/register-address
* # echo VALUE > <debugfs>/ab8500/register-value
*
* read all registers from a bank:
* # echo BANK > <debugfs>/ab8500/register-bank
* # cat <debugfs>/ab8500/all-bank-register
*
* BANK target AB8500 register bank
* ADDR target AB8500 register address
* VALUE decimal or 0x-prefixed hexadecimal
*
*
* User Space notification on AB8500 IRQ
* =====================================
*
* Allows user space entity to be notified when target AB8500 IRQ occurs.
* When subscribed, a sysfs entry is created in ab8500.i2c platform device.
* One can pool this file to get target IRQ occurence information.
*
* subscribe to an AB8500 IRQ:
* # echo IRQ > <debugfs>/ab8500/irq-subscribe
*
* unsubscribe from an AB8500 IRQ:
* # echo IRQ > <debugfs>/ab8500/irq-unsubscribe
*
*
* AB8500 register formated read/write access
* ==========================================
*
* Read: read data, data>>SHIFT, data&=MASK, output data
* [0xABCDEF98] shift=12 mask=0xFFF => 0x00000CDE
* Write: read data, data &= ~(MASK<<SHIFT), data |= (VALUE<<SHIFT), write data
* [0xABCDEF98] shift=12 mask=0xFFF value=0x123 => [0xAB123F98]
*
* Usage:
* # echo "CMD [OPTIONS] BANK ADRESS [VALUE]" > $debugfs/ab8500/hwreg
*
* CMD read read access
* write write access
*
* BANK target reg bank
* ADDRESS target reg address
* VALUE (write) value to be updated
*
* OPTIONS
* -d|-dec (read) output in decimal
* -h|-hexa (read) output in 0x-hexa (default)
* -l|-w|-b 32bit (default), 16bit or 8bit reg access
* -m|-mask MASK 0x-hexa mask (default 0xFFFFFFFF)
* -s|-shift SHIFT bit shift value (read:left, write:right)
* -o|-offset OFFSET address offset to add to ADDRESS value
*
* Warning: bit shift operation is applied to bit-mask.
* Warning: bit shift direction depends on read or right command.
*/
#include <linux/seq_file.h>
#include <linux/uaccess.h>
@ -18,6 +84,11 @@
#include <linux/mfd/abx500.h>
#include <linux/mfd/abx500/ab8500.h>
#ifdef CONFIG_DEBUG_FS
#include <linux/string.h>
#include <linux/ctype.h>
#endif
static u32 debug_bank;
static u32 debug_address;
@ -52,6 +123,25 @@ struct ab8500_prcmu_ranges {
const struct ab8500_reg_range *range;
};
/* hwreg- "mask" and "shift" entries ressources */
struct hwreg_cfg {
u32 bank; /* target bank */
u32 addr; /* target address */
uint fmt; /* format */
uint mask; /* read/write mask, applied before any bit shift */
int shift; /* bit shift (read:right shift, write:left shift */
};
/* fmt bit #0: 0=hexa, 1=dec */
#define REG_FMT_DEC(c) ((c)->fmt & 0x1)
#define REG_FMT_HEX(c) (!REG_FMT_DEC(c))
static struct hwreg_cfg hwreg_cfg = {
.addr = 0, /* default: invalid phys addr */
.fmt = 0, /* default: 32bit access, hex output */
.mask = 0xFFFFFFFF, /* default: no mask */
.shift = 0, /* default: no bit shift */
};
#define AB8500_NAME_STRING "ab8500"
#define AB8500_NUM_BANKS 22
@ -547,6 +637,205 @@ static ssize_t ab8500_val_write(struct file *file,
return count;
}
/*
* - HWREG DB8500 formated routines
*/
static int ab8500_hwreg_print(struct seq_file *s, void *d)
{
struct device *dev = s->private;
int ret;
u8 regvalue;
ret = abx500_get_register_interruptible(dev,
(u8)hwreg_cfg.bank, (u8)hwreg_cfg.addr, &regvalue);
if (ret < 0) {
dev_err(dev, "abx500_get_reg fail %d, %d\n",
ret, __LINE__);
return -EINVAL;
}
if (hwreg_cfg.shift >= 0)
regvalue >>= hwreg_cfg.shift;
else
regvalue <<= -hwreg_cfg.shift;
regvalue &= hwreg_cfg.mask;
if (REG_FMT_DEC(&hwreg_cfg))
seq_printf(s, "%d\n", regvalue);
else
seq_printf(s, "0x%02X\n", regvalue);
return 0;
}
static int ab8500_hwreg_open(struct inode *inode, struct file *file)
{
return single_open(file, ab8500_hwreg_print, inode->i_private);
}
/*
* return length of an ASCII numerical value, 0 is string is not a
* numerical value.
* string shall start at value 1st char.
* string can be tailed with \0 or space or newline chars only.
* value can be decimal or hexadecimal (prefixed 0x or 0X).
*/
static int strval_len(char *b)
{
char *s = b;
if ((*s == '0') && ((*(s+1) == 'x') || (*(s+1) == 'X'))) {
s += 2;
for (; *s && (*s != ' ') && (*s != '\n'); s++) {
if (!isxdigit(*s))
return 0;
}
} else {
if (*s == '-')
s++;
for (; *s && (*s != ' ') && (*s != '\n'); s++) {
if (!isdigit(*s))
return 0;
}
}
return (int) (s-b);
}
/*
* parse hwreg input data.
* update global hwreg_cfg only if input data syntax is ok.
*/
static ssize_t hwreg_common_write(char *b, struct hwreg_cfg *cfg,
struct device *dev)
{
uint write, val = 0;
u8 regvalue;
int ret;
struct hwreg_cfg loc = {
.bank = 0, /* default: invalid phys addr */
.addr = 0, /* default: invalid phys addr */
.fmt = 0, /* default: 32bit access, hex output */
.mask = 0xFFFFFFFF, /* default: no mask */
.shift = 0, /* default: no bit shift */
};
/* read or write ? */
if (!strncmp(b, "read ", 5)) {
write = 0;
b += 5;
} else if (!strncmp(b, "write ", 6)) {
write = 1;
b += 6;
} else
return -EINVAL;
/* OPTIONS -l|-w|-b -s -m -o */
while ((*b == ' ') || (*b == '-')) {
if (*(b-1) != ' ') {
b++;
continue;
}
if ((!strncmp(b, "-d ", 3)) ||
(!strncmp(b, "-dec ", 5))) {
b += (*(b+2) == ' ') ? 3 : 5;
loc.fmt |= (1<<0);
} else if ((!strncmp(b, "-h ", 3)) ||
(!strncmp(b, "-hex ", 5))) {
b += (*(b+2) == ' ') ? 3 : 5;
loc.fmt &= ~(1<<0);
} else if ((!strncmp(b, "-m ", 3)) ||
(!strncmp(b, "-mask ", 6))) {
b += (*(b+2) == ' ') ? 3 : 6;
if (strval_len(b) == 0)
return -EINVAL;
loc.mask = simple_strtoul(b, &b, 0);
} else if ((!strncmp(b, "-s ", 3)) ||
(!strncmp(b, "-shift ", 7))) {
b += (*(b+2) == ' ') ? 3 : 7;
if (strval_len(b) == 0)
return -EINVAL;
loc.shift = simple_strtol(b, &b, 0);
} else {
return -EINVAL;
}
}
/* get arg BANK and ADDRESS */
if (strval_len(b) == 0)
return -EINVAL;
loc.bank = simple_strtoul(b, &b, 0);
while (*b == ' ')
b++;
if (strval_len(b) == 0)
return -EINVAL;
loc.addr = simple_strtoul(b, &b, 0);
if (write) {
while (*b == ' ')
b++;
if (strval_len(b) == 0)
return -EINVAL;
val = simple_strtoul(b, &b, 0);
}
/* args are ok, update target cfg (mainly for read) */
*cfg = loc;
#ifdef ABB_HWREG_DEBUG
pr_warn("HWREG request: %s, %s, addr=0x%08X, mask=0x%X, shift=%d"
"value=0x%X\n", (write) ? "write" : "read",
REG_FMT_DEC(cfg) ? "decimal" : "hexa",
cfg->addr, cfg->mask, cfg->shift, val);
#endif
if (!write)
return 0;
ret = abx500_get_register_interruptible(dev,
(u8)cfg->bank, (u8)cfg->addr, &regvalue);
if (ret < 0) {
dev_err(dev, "abx500_get_reg fail %d, %d\n",
ret, __LINE__);
return -EINVAL;
}
if (cfg->shift >= 0) {
regvalue &= ~(cfg->mask << (cfg->shift));
val = (val & cfg->mask) << (cfg->shift);
} else {
regvalue &= ~(cfg->mask >> (-cfg->shift));
val = (val & cfg->mask) >> (-cfg->shift);
}
val = val | regvalue;
ret = abx500_set_register_interruptible(dev,
(u8)cfg->bank, (u8)cfg->addr, (u8)val);
if (ret < 0) {
pr_err("abx500_set_reg failed %d, %d", ret, __LINE__);
return -EINVAL;
}
return 0;
}
static ssize_t ab8500_hwreg_write(struct file *file,
const char __user *user_buf, size_t count, loff_t *ppos)
{
struct device *dev = ((struct seq_file *)(file->private_data))->private;
char buf[128];
int buf_size, ret;
/* Get userspace string and assure termination */
buf_size = min(count, (sizeof(buf)-1));
if (copy_from_user(buf, user_buf, buf_size))
return -EFAULT;
buf[buf_size] = 0;
/* get args and process */
ret = hwreg_common_write(buf, &hwreg_cfg, dev);
return (ret) ? ret : buf_size;
}
/*
* - irq subscribe/unsubscribe stuff
*/
static int ab8500_subscribe_unsubscribe_print(struct seq_file *s, void *p)
{
seq_printf(s, "%d\n", irq_first);
@ -694,6 +983,10 @@ static ssize_t ab8500_unsubscribe_write(struct file *file,
return buf_size;
}
/*
* - several deubgfs nodes fops
*/
static const struct file_operations ab8500_bank_fops = {
.open = ab8500_bank_open,
.write = ab8500_bank_write,
@ -739,16 +1032,20 @@ static const struct file_operations ab8500_unsubscribe_fops = {
.owner = THIS_MODULE,
};
static const struct file_operations ab8500_hwreg_fops = {
.open = ab8500_hwreg_open,
.write = ab8500_hwreg_write,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
.owner = THIS_MODULE,
};
static struct dentry *ab8500_dir;
static struct dentry *ab8500_reg_file;
static struct dentry *ab8500_bank_file;
static struct dentry *ab8500_address_file;
static struct dentry *ab8500_val_file;
static struct dentry *ab8500_subscribe_file;
static struct dentry *ab8500_unsubscribe_file;
static int ab8500_debug_probe(struct platform_device *plf)
{
struct dentry *file;
debug_bank = AB8500_MISC;
debug_address = AB8500_REV_REG & 0x00FF;
@ -768,70 +1065,59 @@ static int ab8500_debug_probe(struct platform_device *plf)
ab8500_dir = debugfs_create_dir(AB8500_NAME_STRING, NULL);
if (!ab8500_dir)
goto exit_no_debugfs;
goto err;
ab8500_reg_file = debugfs_create_file("all-bank-registers",
file = debugfs_create_file("all-bank-registers",
S_IRUGO, ab8500_dir, &plf->dev, &ab8500_registers_fops);
if (!ab8500_reg_file)
goto exit_destroy_dir;
if (!file)
goto err;
ab8500_bank_file = debugfs_create_file("register-bank",
file = debugfs_create_file("register-bank",
(S_IRUGO | S_IWUSR), ab8500_dir, &plf->dev, &ab8500_bank_fops);
if (!ab8500_bank_file)
goto exit_destroy_reg;
if (!file)
goto err;
ab8500_address_file = debugfs_create_file("register-address",
file = debugfs_create_file("register-address",
(S_IRUGO | S_IWUSR), ab8500_dir, &plf->dev,
&ab8500_address_fops);
if (!ab8500_address_file)
goto exit_destroy_bank;
if (!file)
goto err;
ab8500_val_file = debugfs_create_file("register-value",
file = debugfs_create_file("register-value",
(S_IRUGO | S_IWUSR), ab8500_dir, &plf->dev, &ab8500_val_fops);
if (!ab8500_val_file)
goto exit_destroy_address;
if (!file)
goto err;
ab8500_subscribe_file =
debugfs_create_file("irq-subscribe",
(S_IRUGO | S_IWUGO), ab8500_dir, &plf->dev,
&ab8500_subscribe_fops);
if (!ab8500_subscribe_file)
goto exit_destroy_val;
file = debugfs_create_file("irq-subscribe",
(S_IRUGO | S_IWUSR), ab8500_dir, &plf->dev,
&ab8500_subscribe_fops);
if (!file)
goto err;
ab8500_unsubscribe_file =
debugfs_create_file("irq-unsubscribe",
(S_IRUGO | S_IWUGO), ab8500_dir, &plf->dev,
&ab8500_unsubscribe_fops);
if (!ab8500_unsubscribe_file)
goto exit_destroy_subscribe;
file = debugfs_create_file("irq-unsubscribe",
(S_IRUGO | S_IWUSR), ab8500_dir, &plf->dev,
&ab8500_unsubscribe_fops);
if (!file)
goto err;
file = debugfs_create_file("hwreg",
(S_IRUGO | S_IWUSR), ab8500_dir, &plf->dev,
&ab8500_hwreg_fops);
if (!file)
goto err;
return 0;
exit_destroy_subscribe:
debugfs_remove(ab8500_subscribe_file);
exit_destroy_val:
debugfs_remove(ab8500_val_file);
exit_destroy_address:
debugfs_remove(ab8500_address_file);
exit_destroy_bank:
debugfs_remove(ab8500_bank_file);
exit_destroy_reg:
debugfs_remove(ab8500_reg_file);
exit_destroy_dir:
debugfs_remove(ab8500_dir);
exit_no_debugfs:
err:
if (ab8500_dir)
debugfs_remove_recursive(ab8500_dir);
dev_err(&plf->dev, "failed to create debugfs entries.\n");
return -ENOMEM;
}
static int ab8500_debug_remove(struct platform_device *plf)
{
debugfs_remove(ab8500_val_file);
debugfs_remove(ab8500_address_file);
debugfs_remove(ab8500_bank_file);
debugfs_remove(ab8500_reg_file);
debugfs_remove(ab8500_dir);
debugfs_remove_recursive(ab8500_dir);
return 0;
}