diff options
author | Alessandro Rubini <rubini@gnudd.com> | 2013-06-18 23:47:56 +0200 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-06-19 00:42:15 +0200 |
commit | 6007b1bd0f752a5c022f7944c65fb96c39d6db3d (patch) | |
tree | d0b3074fc8e0589603dbbe4ebc8a3b5c52287842 /drivers/fmc/fmc-write-eeprom.c | |
parent | FMC: add a software mezzanine driver (diff) | |
download | linux-6007b1bd0f752a5c022f7944c65fb96c39d6db3d.tar.xz linux-6007b1bd0f752a5c022f7944c65fb96c39d6db3d.zip |
FMC: add a driver to write mezzanine EEPROM
This driver allows to reprogram the EEPROM in a mezzanine, to store
its own identifiers during manufacturing or to save other useful data.
Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Acked-by: Juan David Gonzalez Cobas <dcobas@cern.ch>
Acked-by: Emilio G. Cota <cota@braap.org>
Acked-by: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/fmc/fmc-write-eeprom.c')
-rw-r--r-- | drivers/fmc/fmc-write-eeprom.c | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/drivers/fmc/fmc-write-eeprom.c b/drivers/fmc/fmc-write-eeprom.c new file mode 100644 index 000000000000..2cc680dd604d --- /dev/null +++ b/drivers/fmc/fmc-write-eeprom.c @@ -0,0 +1,176 @@ +/* + * Copyright (C) 2012 CERN (www.cern.ch) + * Author: Alessandro Rubini <rubini@gnudd.com> + * + * Released according to the GNU GPL, version 2 or any later version. + * + * This work is part of the White Rabbit project, a research effort led + * by CERN, the European Institute for Nuclear Research. + */ +#include <linux/module.h> +#include <linux/string.h> +#include <linux/firmware.h> +#include <linux/init.h> +#include <linux/fmc.h> +#include <asm/unaligned.h> + +/* + * This module uses the firmware loader to program the whole or part + * of the FMC eeprom. The meat is in the _run functions. However, no + * default file name is provided, to avoid accidental mishaps. Also, + * you must pass the busid argument + */ +static struct fmc_driver fwe_drv; + +FMC_PARAM_BUSID(fwe_drv); + +/* The "file=" is like the generic "gateware=" used elsewhere */ +static char *fwe_file[FMC_MAX_CARDS]; +static int fwe_file_n; +module_param_array_named(file, fwe_file, charp, &fwe_file_n, 444); + +static int fwe_run_tlv(struct fmc_device *fmc, const struct firmware *fw, + int write) +{ + const uint8_t *p = fw->data; + int len = fw->size; + uint16_t thislen, thisaddr; + int err; + + /* format is: 'w' addr16 len16 data... */ + while (len > 5) { + thisaddr = get_unaligned_le16(p+1); + thislen = get_unaligned_le16(p+3); + if (p[0] != 'w' || thislen + 5 > len) { + dev_err(&fmc->dev, "invalid tlv at offset %ti\n", + p - fw->data); + return -EINVAL; + } + err = 0; + if (write) { + dev_info(&fmc->dev, "write %i bytes at 0x%04x\n", + thislen, thisaddr); + err = fmc->op->write_ee(fmc, thisaddr, p + 5, thislen); + } + if (err < 0) { + dev_err(&fmc->dev, "write failure @0x%04x\n", + thisaddr); + return err; + } + p += 5 + thislen; + len -= 5 + thislen; + } + if (write) + dev_info(&fmc->dev, "write_eeprom: success\n"); + return 0; +} + +static int fwe_run_bin(struct fmc_device *fmc, const struct firmware *fw) +{ + int ret; + + dev_info(&fmc->dev, "programming %zi bytes\n", fw->size); + ret = fmc->op->write_ee(fmc, 0, (void *)fw->data, fw->size); + if (ret < 0) { + dev_info(&fmc->dev, "write_eeprom: error %i\n", ret); + return ret; + } + dev_info(&fmc->dev, "write_eeprom: success\n"); + return 0; +} + +static int fwe_run(struct fmc_device *fmc, const struct firmware *fw, char *s) +{ + char *last4 = s + strlen(s) - 4; + int err; + + if (!strcmp(last4, ".bin")) + return fwe_run_bin(fmc, fw); + if (!strcmp(last4, ".tlv")) { + err = fwe_run_tlv(fmc, fw, 0); + if (!err) + err = fwe_run_tlv(fmc, fw, 1); + return err; + } + dev_err(&fmc->dev, "invalid file name \"%s\"\n", s); + return -EINVAL; +} + +/* + * Programming is done at probe time. Morever, only those listed with + * busid= are programmed. + * card is probed for, only one is programmed. Unfortunately, it's + * difficult to know in advance when probing the first card if others + * are there. + */ +int fwe_probe(struct fmc_device *fmc) +{ + int err, index = 0; + const struct firmware *fw; + struct device *dev = &fmc->dev; + char *s; + + if (!fwe_drv.busid_n) { + dev_err(dev, "%s: no busid passed, refusing all cards\n", + KBUILD_MODNAME); + return -ENODEV; + } + if (fmc->op->validate) + index = fmc->op->validate(fmc, &fwe_drv); + if (index < 0) { + pr_err("%s: refusing device \"%s\"\n", KBUILD_MODNAME, + dev_name(dev)); + return -ENODEV; + } + if (index >= fwe_file_n) { + pr_err("%s: no filename for device index %i\n", + KBUILD_MODNAME, index); + return -ENODEV; + } + s = fwe_file[index]; + if (!s) { + pr_err("%s: no filename for \"%s\" not programming\n", + KBUILD_MODNAME, dev_name(dev)); + return -ENOENT; + } + err = request_firmware(&fw, s, dev); + if (err < 0) { + dev_err(&fmc->dev, "request firmware \"%s\": error %i\n", + s, err); + return err; + } + fwe_run(fmc, fw, s); + release_firmware(fw); + return 0; +} + +int fwe_remove(struct fmc_device *fmc) +{ + return 0; +} + +static struct fmc_driver fwe_drv = { + .version = FMC_VERSION, + .driver.name = KBUILD_MODNAME, + .probe = fwe_probe, + .remove = fwe_remove, + /* no table, as the current match just matches everything */ +}; + +static int fwe_init(void) +{ + int ret; + + ret = fmc_driver_register(&fwe_drv); + return ret; +} + +static void fwe_exit(void) +{ + fmc_driver_unregister(&fwe_drv); +} + +module_init(fwe_init); +module_exit(fwe_exit); + +MODULE_LICENSE("GPL"); |