From 0fbce76eff0e7ea92f51b253c504a79d9b3b5769 Mon Sep 17 00:00:00 2001 From: carriere etienne Date: Fri, 8 Apr 2011 16:26:36 +0200 Subject: [PATCH] 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 Signed-off-by: carriere etienne Reviewed-by: Mattias WALLIN --- drivers/mfd/ab8500-debugfs.c | 386 ++++++++++++++++++++++++++++++----- 1 file changed, 336 insertions(+), 50 deletions(-) diff --git a/drivers/mfd/ab8500-debugfs.c b/drivers/mfd/ab8500-debugfs.c index 1bb74297a3a7..79a954f79732 100644 --- a/drivers/mfd/ab8500-debugfs.c +++ b/drivers/mfd/ab8500-debugfs.c @@ -4,6 +4,72 @@ * Author: Mattias Wallin for ST-Ericsson. * License Terms: GNU General Public License v2 */ +/* + * AB8500 register access + * ====================== + * + * read: + * # echo BANK > /ab8500/register-bank + * # echo ADDR > /ab8500/register-address + * # cat /ab8500/register-value + * + * write: + * # echo BANK > /ab8500/register-bank + * # echo ADDR > /ab8500/register-address + * # echo VALUE > /ab8500/register-value + * + * read all registers from a bank: + * # echo BANK > /ab8500/register-bank + * # cat /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 > /ab8500/irq-subscribe + * + * unsubscribe from an AB8500 IRQ: + * # echo IRQ > /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< [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 #include @@ -18,6 +84,11 @@ #include #include +#ifdef CONFIG_DEBUG_FS +#include +#include +#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, ®value); + 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, ®value); + 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; }