diff options
| -rw-r--r-- | drivers/mtd/chips/cfi_cmdset_0001.c | 146 |
1 files changed, 77 insertions, 69 deletions
diff --git a/drivers/mtd/chips/cfi_cmdset_0001.c b/drivers/mtd/chips/cfi_cmdset_0001.c index 3aa3dca56ae..a9eb1c51624 100644 --- a/drivers/mtd/chips/cfi_cmdset_0001.c +++ b/drivers/mtd/chips/cfi_cmdset_0001.c @@ -85,6 +85,7 @@ static int cfi_intelext_point (struct mtd_info *mtd, loff_t from, size_t len, static void cfi_intelext_unpoint (struct mtd_info *mtd, u_char *addr, loff_t from, size_t len); +static int chip_ready (struct map_info *map, struct flchip *chip, unsigned long adr, int mode); static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr, int mode); static void put_chip(struct map_info *map, struct flchip *chip, unsigned long adr); #include "fwh_lock.h" @@ -641,73 +642,13 @@ static int cfi_intelext_partition_fixup(struct mtd_info *mtd, /* * *********** CHIP ACCESS FUNCTIONS *********** */ - -static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr, int mode) +static int chip_ready (struct map_info *map, struct flchip *chip, unsigned long adr, int mode) { DECLARE_WAITQUEUE(wait, current); struct cfi_private *cfi = map->fldrv_priv; map_word status, status_OK = CMD(0x80), status_PWS = CMD(0x01); - unsigned long timeo; struct cfi_pri_intelext *cfip = cfi->cmdset_priv; - - resettime: - timeo = jiffies + HZ; - retry: - if (chip->priv && (mode == FL_WRITING || mode == FL_ERASING || mode == FL_OTP_WRITE || mode == FL_SHUTDOWN)) { - /* - * OK. We have possibility for contension on the write/erase - * operations which are global to the real chip and not per - * partition. So let's fight it over in the partition which - * currently has authority on the operation. - * - * The rules are as follows: - * - * - any write operation must own shared->writing. - * - * - any erase operation must own _both_ shared->writing and - * shared->erasing. - * - * - contension arbitration is handled in the owner's context. - * - * The 'shared' struct can be read and/or written only when - * its lock is taken. - */ - struct flchip_shared *shared = chip->priv; - struct flchip *contender; - spin_lock(&shared->lock); - contender = shared->writing; - if (contender && contender != chip) { - /* - * The engine to perform desired operation on this - * partition is already in use by someone else. - * Let's fight over it in the context of the chip - * currently using it. If it is possible to suspend, - * that other partition will do just that, otherwise - * it'll happily send us to sleep. In any case, when - * get_chip returns success we're clear to go ahead. - */ - int ret = spin_trylock(contender->mutex); - spin_unlock(&shared->lock); - if (!ret) - goto retry; - spin_unlock(chip->mutex); - ret = get_chip(map, contender, contender->start, mode); - spin_lock(chip->mutex); - if (ret) { - spin_unlock(contender->mutex); - return ret; - } - timeo = jiffies + HZ; - spin_lock(&shared->lock); - spin_unlock(contender->mutex); - } - - /* We now own it */ - shared->writing = chip; - if (mode == FL_ERASING) - shared->erasing = chip; - spin_unlock(&shared->lock); - } + unsigned long timeo = jiffies + HZ; switch (chip->state) { @@ -722,16 +663,11 @@ static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr if (chip->priv && map_word_andequal(map, status, status_PWS, status_PWS)) break; - if (time_after(jiffies, timeo)) { - printk(KERN_ERR "%s: Waiting for chip to be ready timed out. Status %lx\n", - map->name, status.x[0]); - return -EIO; - } spin_unlock(chip->mutex); cfi_udelay(1); spin_lock(chip->mutex); /* Someone else might have been playing with it. */ - goto retry; + return -EAGAIN; } case FL_READY: @@ -809,10 +745,82 @@ static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr schedule(); remove_wait_queue(&chip->wq, &wait); spin_lock(chip->mutex); - goto resettime; + return -EAGAIN; } } +static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr, int mode) +{ + int ret; + + retry: + if (chip->priv && (mode == FL_WRITING || mode == FL_ERASING + || mode == FL_OTP_WRITE || mode == FL_SHUTDOWN)) { + /* + * OK. We have possibility for contention on the write/erase + * operations which are global to the real chip and not per + * partition. So let's fight it over in the partition which + * currently has authority on the operation. + * + * The rules are as follows: + * + * - any write operation must own shared->writing. + * + * - any erase operation must own _both_ shared->writing and + * shared->erasing. + * + * - contention arbitration is handled in the owner's context. + * + * The 'shared' struct can be read and/or written only when + * its lock is taken. + */ + struct flchip_shared *shared = chip->priv; + struct flchip *contender; + spin_lock(&shared->lock); + contender = shared->writing; + if (contender && contender != chip) { + /* + * The engine to perform desired operation on this + * partition is already in use by someone else. + * Let's fight over it in the context of the chip + * currently using it. If it is possible to suspend, + * that other partition will do just that, otherwise + * it'll happily send us to sleep. In any case, when + * get_chip returns success we're clear to go ahead. + */ + ret = spin_trylock(contender->mutex); + spin_unlock(&shared->lock); + if (!ret) + goto retry; + spin_unlock(chip->mutex); + ret = chip_ready(map, contender, contender->start, mode); + spin_lock(chip->mutex); + + if (ret == -EAGAIN) { + spin_unlock(contender->mutex); + goto retry; + } + if (ret) { + spin_unlock(contender->mutex); + return ret; + } + spin_lock(&shared->lock); + spin_unlock(contender->mutex); + } + + /* We now own it */ + shared->writing = chip; + if (mode == FL_ERASING) + shared->erasing = chip; + spin_unlock(&shared->lock); + } + ret = chip_ready(map, chip, adr, mode); + if (ret == -EAGAIN) + goto retry; + + return ret; +} + static void put_chip(struct map_info *map, struct flchip *chip, unsigned long adr) { struct cfi_private *cfi = map->fldrv_priv; |