Thomas Gleixner | 1802d0b | 2019-05-27 08:55:21 +0200 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-only |
Matt Redfearn | 2aefbef | 2016-10-19 13:05:47 +0100 | [diff] [blame] | 2 | /* |
| 3 | * Remote Processor Framework |
Matt Redfearn | 2aefbef | 2016-10-19 13:05:47 +0100 | [diff] [blame] | 4 | */ |
| 5 | |
| 6 | #include <linux/remoteproc.h> |
| 7 | |
| 8 | #include "remoteproc_internal.h" |
| 9 | |
| 10 | #define to_rproc(d) container_of(d, struct rproc, dev) |
| 11 | |
| 12 | /* Expose the loaded / running firmware name via sysfs */ |
| 13 | static ssize_t firmware_show(struct device *dev, struct device_attribute *attr, |
| 14 | char *buf) |
| 15 | { |
| 16 | struct rproc *rproc = to_rproc(dev); |
| 17 | |
| 18 | return sprintf(buf, "%s\n", rproc->firmware); |
| 19 | } |
| 20 | |
| 21 | /* Change firmware name via sysfs */ |
| 22 | static ssize_t firmware_store(struct device *dev, |
| 23 | struct device_attribute *attr, |
| 24 | const char *buf, size_t count) |
| 25 | { |
| 26 | struct rproc *rproc = to_rproc(dev); |
| 27 | char *p; |
| 28 | int err, len = count; |
| 29 | |
| 30 | err = mutex_lock_interruptible(&rproc->lock); |
| 31 | if (err) { |
| 32 | dev_err(dev, "can't lock rproc %s: %d\n", rproc->name, err); |
| 33 | return -EINVAL; |
| 34 | } |
| 35 | |
| 36 | if (rproc->state != RPROC_OFFLINE) { |
| 37 | dev_err(dev, "can't change firmware while running\n"); |
| 38 | err = -EBUSY; |
| 39 | goto out; |
| 40 | } |
| 41 | |
| 42 | len = strcspn(buf, "\n"); |
Suman Anna | faeadbb | 2018-09-14 19:37:22 -0500 | [diff] [blame] | 43 | if (!len) { |
| 44 | dev_err(dev, "can't provide a NULL firmware\n"); |
| 45 | err = -EINVAL; |
| 46 | goto out; |
| 47 | } |
Matt Redfearn | 2aefbef | 2016-10-19 13:05:47 +0100 | [diff] [blame] | 48 | |
| 49 | p = kstrndup(buf, len, GFP_KERNEL); |
| 50 | if (!p) { |
| 51 | err = -ENOMEM; |
| 52 | goto out; |
| 53 | } |
| 54 | |
| 55 | kfree(rproc->firmware); |
| 56 | rproc->firmware = p; |
| 57 | out: |
| 58 | mutex_unlock(&rproc->lock); |
| 59 | |
| 60 | return err ? err : count; |
| 61 | } |
| 62 | static DEVICE_ATTR_RW(firmware); |
| 63 | |
| 64 | /* |
| 65 | * A state-to-string lookup table, for exposing a human readable state |
| 66 | * via sysfs. Always keep in sync with enum rproc_state |
| 67 | */ |
| 68 | static const char * const rproc_state_string[] = { |
| 69 | [RPROC_OFFLINE] = "offline", |
| 70 | [RPROC_SUSPENDED] = "suspended", |
| 71 | [RPROC_RUNNING] = "running", |
| 72 | [RPROC_CRASHED] = "crashed", |
Sarangdhar Joshi | 608d792 | 2017-01-23 17:53:18 -0800 | [diff] [blame] | 73 | [RPROC_DELETED] = "deleted", |
Matt Redfearn | 2aefbef | 2016-10-19 13:05:47 +0100 | [diff] [blame] | 74 | [RPROC_LAST] = "invalid", |
| 75 | }; |
| 76 | |
| 77 | /* Expose the state of the remote processor via sysfs */ |
| 78 | static ssize_t state_show(struct device *dev, struct device_attribute *attr, |
| 79 | char *buf) |
| 80 | { |
| 81 | struct rproc *rproc = to_rproc(dev); |
| 82 | unsigned int state; |
| 83 | |
| 84 | state = rproc->state > RPROC_LAST ? RPROC_LAST : rproc->state; |
| 85 | return sprintf(buf, "%s\n", rproc_state_string[state]); |
| 86 | } |
| 87 | |
| 88 | /* Change remote processor state via sysfs */ |
| 89 | static ssize_t state_store(struct device *dev, |
| 90 | struct device_attribute *attr, |
| 91 | const char *buf, size_t count) |
| 92 | { |
| 93 | struct rproc *rproc = to_rproc(dev); |
| 94 | int ret = 0; |
| 95 | |
| 96 | if (sysfs_streq(buf, "start")) { |
| 97 | if (rproc->state == RPROC_RUNNING) |
| 98 | return -EBUSY; |
| 99 | |
| 100 | ret = rproc_boot(rproc); |
| 101 | if (ret) |
| 102 | dev_err(&rproc->dev, "Boot failed: %d\n", ret); |
| 103 | } else if (sysfs_streq(buf, "stop")) { |
| 104 | if (rproc->state != RPROC_RUNNING) |
| 105 | return -EINVAL; |
| 106 | |
| 107 | rproc_shutdown(rproc); |
| 108 | } else { |
| 109 | dev_err(&rproc->dev, "Unrecognised option: %s\n", buf); |
| 110 | ret = -EINVAL; |
| 111 | } |
| 112 | return ret ? ret : count; |
| 113 | } |
| 114 | static DEVICE_ATTR_RW(state); |
| 115 | |
| 116 | static struct attribute *rproc_attrs[] = { |
| 117 | &dev_attr_firmware.attr, |
| 118 | &dev_attr_state.attr, |
| 119 | NULL |
| 120 | }; |
| 121 | |
| 122 | static const struct attribute_group rproc_devgroup = { |
| 123 | .attrs = rproc_attrs |
| 124 | }; |
| 125 | |
| 126 | static const struct attribute_group *rproc_devgroups[] = { |
| 127 | &rproc_devgroup, |
| 128 | NULL |
| 129 | }; |
| 130 | |
| 131 | struct class rproc_class = { |
| 132 | .name = "remoteproc", |
| 133 | .dev_groups = rproc_devgroups, |
| 134 | }; |
| 135 | |
| 136 | int __init rproc_init_sysfs(void) |
| 137 | { |
| 138 | /* create remoteproc device class for sysfs */ |
| 139 | int err = class_register(&rproc_class); |
| 140 | |
| 141 | if (err) |
| 142 | pr_err("remoteproc: unable to register class\n"); |
| 143 | return err; |
| 144 | } |
| 145 | |
| 146 | void __exit rproc_exit_sysfs(void) |
| 147 | { |
| 148 | class_unregister(&rproc_class); |
| 149 | } |