Greg Kroah-Hartman | d5d1903 | 2014-08-11 19:03:20 +0800 | [diff] [blame] | 1 | /* |
| 2 | * Greybus gbuf handling |
| 3 | * |
| 4 | * Copyright 2014 Google Inc. |
| 5 | * |
| 6 | * Released under the GPLv2 only. |
| 7 | */ |
| 8 | |
| 9 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 10 | |
| 11 | #include <linux/types.h> |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/moduleparam.h> |
| 14 | #include <linux/kernel.h> |
Greg Kroah-Hartman | a39879f | 2014-09-06 16:57:36 -0700 | [diff] [blame] | 15 | #include <linux/kref.h> |
Greg Kroah-Hartman | d5d1903 | 2014-08-11 19:03:20 +0800 | [diff] [blame] | 16 | #include <linux/device.h> |
Greg Kroah-Hartman | a39879f | 2014-09-06 16:57:36 -0700 | [diff] [blame] | 17 | #include <linux/slab.h> |
Greg Kroah-Hartman | 45f3678 | 2014-09-14 11:40:35 -0700 | [diff] [blame] | 18 | #include <linux/workqueue.h> |
Greg Kroah-Hartman | d5d1903 | 2014-08-11 19:03:20 +0800 | [diff] [blame] | 19 | |
| 20 | #include "greybus.h" |
| 21 | |
Alex Elder | 2e35368 | 2014-09-23 12:46:36 -0500 | [diff] [blame] | 22 | static void cport_process_event(struct work_struct *work); |
Greg Kroah-Hartman | 3e7736e | 2014-09-21 17:34:28 -0700 | [diff] [blame] | 23 | |
| 24 | static struct kmem_cache *gbuf_head_cache; |
| 25 | |
Alex Elder | 2e35368 | 2014-09-23 12:46:36 -0500 | [diff] [blame] | 26 | /* Workqueue to handle Greybus buffer completions. */ |
| 27 | static struct workqueue_struct *gbuf_workqueue; |
| 28 | |
Greg Kroah-Hartman | a39879f | 2014-09-06 16:57:36 -0700 | [diff] [blame] | 29 | /** |
| 30 | * greybus_alloc_gbuf - allocate a greybus buffer |
| 31 | * |
Alex Elder | 778c69c | 2014-09-22 19:19:03 -0500 | [diff] [blame] | 32 | * @gmod: greybus device that wants to allocate this |
Greg Kroah-Hartman | a39879f | 2014-09-06 16:57:36 -0700 | [diff] [blame] | 33 | * @cport: cport to send the data to |
| 34 | * @complete: callback when the gbuf is finished with |
| 35 | * @size: size of the buffer |
| 36 | * @gfp_mask: allocation mask |
| 37 | * @context: context added to the gbuf by the driver |
| 38 | * |
| 39 | * TODO: someday it will be nice to handle DMA, but for now, due to the |
| 40 | * architecture we are stuck with, the greybus core has to allocate the buffer |
| 41 | * that the driver can then fill up with the data to be sent out. Curse |
| 42 | * hardware designers for this issue... |
| 43 | */ |
Alex Elder | 6eb3f4b | 2014-10-06 06:53:10 -0500 | [diff] [blame] | 44 | struct gbuf *greybus_alloc_gbuf(struct gb_connection *connection, |
Greg Kroah-Hartman | a39879f | 2014-09-06 16:57:36 -0700 | [diff] [blame] | 45 | gbuf_complete_t complete, |
| 46 | unsigned int size, |
Alex Elder | 9a6f631 | 2014-10-06 06:53:11 -0500 | [diff] [blame] | 47 | bool outbound, |
Greg Kroah-Hartman | a39879f | 2014-09-06 16:57:36 -0700 | [diff] [blame] | 48 | gfp_t gfp_mask, |
| 49 | void *context) |
Greg Kroah-Hartman | d5d1903 | 2014-08-11 19:03:20 +0800 | [diff] [blame] | 50 | { |
Greg Kroah-Hartman | a39879f | 2014-09-06 16:57:36 -0700 | [diff] [blame] | 51 | struct gbuf *gbuf; |
| 52 | int retval; |
| 53 | |
Alex Elder | fdb594f | 2014-10-06 06:53:12 -0500 | [diff] [blame] | 54 | gbuf = kmem_cache_zalloc(gbuf_head_cache, gfp_mask); |
Greg Kroah-Hartman | a39879f | 2014-09-06 16:57:36 -0700 | [diff] [blame] | 55 | if (!gbuf) |
| 56 | return NULL; |
| 57 | |
Alex Elder | fdb594f | 2014-10-06 06:53:12 -0500 | [diff] [blame] | 58 | kref_init(&gbuf->kref); |
| 59 | gbuf->connection = connection; |
| 60 | INIT_WORK(&gbuf->event, cport_process_event); |
| 61 | gbuf->outbound = outbound; |
| 62 | gbuf->complete = complete; |
| 63 | gbuf->context = context; |
| 64 | |
Greg Kroah-Hartman | a39879f | 2014-09-06 16:57:36 -0700 | [diff] [blame] | 65 | /* Host controller specific allocation for the actual buffer */ |
Alex Elder | 6eb3f4b | 2014-10-06 06:53:10 -0500 | [diff] [blame] | 66 | retval = connection->hd->driver->alloc_gbuf_data(gbuf, size, gfp_mask); |
Greg Kroah-Hartman | a39879f | 2014-09-06 16:57:36 -0700 | [diff] [blame] | 67 | if (retval) { |
Alex Elder | fdb594f | 2014-10-06 06:53:12 -0500 | [diff] [blame] | 68 | kmem_cache_free(gbuf_head_cache, gbuf); |
Greg Kroah-Hartman | a39879f | 2014-09-06 16:57:36 -0700 | [diff] [blame] | 69 | return NULL; |
| 70 | } |
| 71 | |
| 72 | return gbuf; |
| 73 | } |
| 74 | EXPORT_SYMBOL_GPL(greybus_alloc_gbuf); |
| 75 | |
| 76 | static DEFINE_MUTEX(gbuf_mutex); |
| 77 | |
| 78 | static void free_gbuf(struct kref *kref) |
| 79 | { |
| 80 | struct gbuf *gbuf = container_of(kref, struct gbuf, kref); |
| 81 | |
Alex Elder | 9a6f631 | 2014-10-06 06:53:11 -0500 | [diff] [blame] | 82 | gbuf->connection->hd->driver->free_gbuf_data(gbuf); |
Greg Kroah-Hartman | a39879f | 2014-09-06 16:57:36 -0700 | [diff] [blame] | 83 | |
Greg Kroah-Hartman | 3e7736e | 2014-09-21 17:34:28 -0700 | [diff] [blame] | 84 | kmem_cache_free(gbuf_head_cache, gbuf); |
Alex Elder | ad8cd0d6 | 2014-10-16 06:35:25 -0500 | [diff] [blame] | 85 | mutex_unlock(&gbuf_mutex); |
Greg Kroah-Hartman | d5d1903 | 2014-08-11 19:03:20 +0800 | [diff] [blame] | 86 | } |
| 87 | |
| 88 | void greybus_free_gbuf(struct gbuf *gbuf) |
| 89 | { |
Greg Kroah-Hartman | a39879f | 2014-09-06 16:57:36 -0700 | [diff] [blame] | 90 | /* drop the reference count and get out of here */ |
| 91 | kref_put_mutex(&gbuf->kref, free_gbuf, &gbuf_mutex); |
Greg Kroah-Hartman | d5d1903 | 2014-08-11 19:03:20 +0800 | [diff] [blame] | 92 | } |
Greg Kroah-Hartman | a39879f | 2014-09-06 16:57:36 -0700 | [diff] [blame] | 93 | EXPORT_SYMBOL_GPL(greybus_free_gbuf); |
| 94 | |
| 95 | struct gbuf *greybus_get_gbuf(struct gbuf *gbuf) |
| 96 | { |
| 97 | mutex_lock(&gbuf_mutex); |
| 98 | kref_get(&gbuf->kref); |
| 99 | mutex_unlock(&gbuf_mutex); |
| 100 | return gbuf; |
| 101 | } |
| 102 | EXPORT_SYMBOL_GPL(greybus_get_gbuf); |
| 103 | |
Greg Kroah-Hartman | f036e05 | 2014-09-19 19:13:33 -0700 | [diff] [blame] | 104 | int greybus_submit_gbuf(struct gbuf *gbuf, gfp_t gfp_mask) |
Greg Kroah-Hartman | d5d1903 | 2014-08-11 19:03:20 +0800 | [diff] [blame] | 105 | { |
Alex Elder | 6eb3f4b | 2014-10-06 06:53:10 -0500 | [diff] [blame] | 106 | struct greybus_host_device *hd = gbuf->connection->hd; |
| 107 | |
| 108 | return hd->driver->submit_gbuf(gbuf, hd, gfp_mask); |
Greg Kroah-Hartman | d5d1903 | 2014-08-11 19:03:20 +0800 | [diff] [blame] | 109 | } |
| 110 | |
| 111 | int greybus_kill_gbuf(struct gbuf *gbuf) |
| 112 | { |
Greg Kroah-Hartman | 9c8d3af | 2014-09-13 11:09:35 -0700 | [diff] [blame] | 113 | // FIXME - implement |
Greg Kroah-Hartman | d5d1903 | 2014-08-11 19:03:20 +0800 | [diff] [blame] | 114 | return -ENOMEM; |
| 115 | } |
Greg Kroah-Hartman | 9c8d3af | 2014-09-13 11:09:35 -0700 | [diff] [blame] | 116 | |
Greg Kroah-Hartman | 3e7736e | 2014-09-21 17:34:28 -0700 | [diff] [blame] | 117 | static void cport_process_event(struct work_struct *work) |
| 118 | { |
Alex Elder | 2e35368 | 2014-09-23 12:46:36 -0500 | [diff] [blame] | 119 | struct gbuf *gbuf = container_of(work, struct gbuf, event); |
Greg Kroah-Hartman | 3e7736e | 2014-09-21 17:34:28 -0700 | [diff] [blame] | 120 | |
Alex Elder | 2e35368 | 2014-09-23 12:46:36 -0500 | [diff] [blame] | 121 | /* Call the completion handler, then drop our reference */ |
Greg Kroah-Hartman | dce745a | 2014-09-23 20:58:58 -0700 | [diff] [blame] | 122 | gbuf->complete(gbuf); |
| 123 | greybus_put_gbuf(gbuf); |
Greg Kroah-Hartman | 3e7736e | 2014-09-21 17:34:28 -0700 | [diff] [blame] | 124 | } |
| 125 | |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 126 | #define MAX_CPORTS 1024 |
| 127 | struct gb_cport_handler { |
| 128 | gbuf_complete_t handler; |
Alex Elder | 1cfc667 | 2014-09-30 19:25:21 -0500 | [diff] [blame] | 129 | u16 cport_id; |
Alex Elder | e1e9dbd | 2014-10-01 21:54:11 -0500 | [diff] [blame] | 130 | struct gb_module *gmod; |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 131 | void *context; |
| 132 | }; |
| 133 | |
| 134 | static struct gb_cport_handler cport_handler[MAX_CPORTS]; |
| 135 | // FIXME - use a lock for this list of handlers, but really, for now we don't |
| 136 | // need it, we don't have a dynamic system... |
| 137 | |
Alex Elder | e1e9dbd | 2014-10-01 21:54:11 -0500 | [diff] [blame] | 138 | int gb_register_cport_complete(struct gb_module *gmod, |
| 139 | gbuf_complete_t handler, |
| 140 | u16 cport_id, |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 141 | void *context) |
| 142 | { |
Alex Elder | 0db32a6 | 2014-09-24 05:16:14 -0500 | [diff] [blame] | 143 | if (cport_handler[cport_id].handler) |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 144 | return -EINVAL; |
Alex Elder | 0db32a6 | 2014-09-24 05:16:14 -0500 | [diff] [blame] | 145 | cport_handler[cport_id].context = context; |
| 146 | cport_handler[cport_id].gmod = gmod; |
Alex Elder | 1cfc667 | 2014-09-30 19:25:21 -0500 | [diff] [blame] | 147 | cport_handler[cport_id].cport_id = cport_id; |
Alex Elder | 0db32a6 | 2014-09-24 05:16:14 -0500 | [diff] [blame] | 148 | cport_handler[cport_id].handler = handler; |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 149 | return 0; |
| 150 | } |
| 151 | |
Alex Elder | 1cfc667 | 2014-09-30 19:25:21 -0500 | [diff] [blame] | 152 | void gb_deregister_cport_complete(u16 cport_id) |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 153 | { |
Alex Elder | 0db32a6 | 2014-09-24 05:16:14 -0500 | [diff] [blame] | 154 | cport_handler[cport_id].handler = NULL; |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 155 | } |
| 156 | |
Alex Elder | 1cfc667 | 2014-09-30 19:25:21 -0500 | [diff] [blame] | 157 | void greybus_cport_in(struct greybus_host_device *hd, u16 cport_id, |
| 158 | u8 *data, size_t length) |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 159 | { |
| 160 | struct gb_cport_handler *ch; |
| 161 | struct gbuf *gbuf; |
Alex Elder | 00d2e75 | 2014-10-06 06:53:09 -0500 | [diff] [blame] | 162 | struct gb_connection *connection; |
| 163 | |
| 164 | connection = gb_hd_connection_find(hd, cport_id); |
| 165 | if (!connection) { |
| 166 | dev_err(hd->parent, |
| 167 | "nonexistent connection (%zu bytes dropped)\n", length); |
| 168 | return; |
| 169 | } |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 170 | |
| 171 | /* first check to see if we have a cport handler for this cport */ |
Alex Elder | 0db32a6 | 2014-09-24 05:16:14 -0500 | [diff] [blame] | 172 | ch = &cport_handler[cport_id]; |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 173 | if (!ch->handler) { |
| 174 | /* Ugh, drop the data on the floor, after logging it... */ |
Greg Kroah-Hartman | 772149b | 2014-09-14 12:27:28 -0700 | [diff] [blame] | 175 | dev_err(hd->parent, |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 176 | "Received data for cport %d, but no handler!\n", |
Alex Elder | 0db32a6 | 2014-09-24 05:16:14 -0500 | [diff] [blame] | 177 | cport_id); |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 178 | return; |
| 179 | } |
| 180 | |
Alex Elder | 9a6f631 | 2014-10-06 06:53:11 -0500 | [diff] [blame] | 181 | gbuf = greybus_alloc_gbuf(connection, ch->handler, length, false, |
| 182 | GFP_ATOMIC, ch->context); |
| 183 | |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 184 | if (!gbuf) { |
| 185 | /* Again, something bad went wrong, log it... */ |
| 186 | pr_err("can't allocate gbuf???\n"); |
| 187 | return; |
| 188 | } |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 189 | |
Greg Kroah-Hartman | 45f3678 | 2014-09-14 11:40:35 -0700 | [diff] [blame] | 190 | /* |
| 191 | * FIXME: |
| 192 | * Very dumb copy data method for now, if this is slow (odds are it will |
| 193 | * be, we should move to a model where the hd "owns" all buffers, but we |
| 194 | * want something up and working first for now. |
| 195 | */ |
Greg Kroah-Hartman | 45f3678 | 2014-09-14 11:40:35 -0700 | [diff] [blame] | 196 | memcpy(gbuf->transfer_buffer, data, length); |
Greg Kroah-Hartman | 3e7736e | 2014-09-21 17:34:28 -0700 | [diff] [blame] | 197 | gbuf->actual_length = length; |
Greg Kroah-Hartman | 45f3678 | 2014-09-14 11:40:35 -0700 | [diff] [blame] | 198 | |
Alex Elder | 2e35368 | 2014-09-23 12:46:36 -0500 | [diff] [blame] | 199 | queue_work(gbuf_workqueue, &gbuf->event); |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 200 | } |
Alex Elder | 0db32a6 | 2014-09-24 05:16:14 -0500 | [diff] [blame] | 201 | EXPORT_SYMBOL_GPL(greybus_cport_in); |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 202 | |
Greg Kroah-Hartman | f036e05 | 2014-09-19 19:13:33 -0700 | [diff] [blame] | 203 | /* Can be called in interrupt context, do the work and get out of here */ |
| 204 | void greybus_gbuf_finished(struct gbuf *gbuf) |
| 205 | { |
Alex Elder | 2e35368 | 2014-09-23 12:46:36 -0500 | [diff] [blame] | 206 | queue_work(gbuf_workqueue, &gbuf->event); |
Greg Kroah-Hartman | f036e05 | 2014-09-19 19:13:33 -0700 | [diff] [blame] | 207 | } |
| 208 | EXPORT_SYMBOL_GPL(greybus_gbuf_finished); |
| 209 | |
Greg Kroah-Hartman | 45f3678 | 2014-09-14 11:40:35 -0700 | [diff] [blame] | 210 | int gb_gbuf_init(void) |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 211 | { |
Alex Elder | 2e35368 | 2014-09-23 12:46:36 -0500 | [diff] [blame] | 212 | gbuf_workqueue = alloc_workqueue("greybus_gbuf", 0, 1); |
| 213 | if (!gbuf_workqueue) |
Greg Kroah-Hartman | 45f3678 | 2014-09-14 11:40:35 -0700 | [diff] [blame] | 214 | return -ENOMEM; |
| 215 | |
Greg Kroah-Hartman | 3e7736e | 2014-09-21 17:34:28 -0700 | [diff] [blame] | 216 | gbuf_head_cache = kmem_cache_create("gbuf_head_cache", |
| 217 | sizeof(struct gbuf), 0, 0, NULL); |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 218 | return 0; |
| 219 | } |
| 220 | |
Greg Kroah-Hartman | 45f3678 | 2014-09-14 11:40:35 -0700 | [diff] [blame] | 221 | void gb_gbuf_exit(void) |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 222 | { |
Alex Elder | 2e35368 | 2014-09-23 12:46:36 -0500 | [diff] [blame] | 223 | destroy_workqueue(gbuf_workqueue); |
Greg Kroah-Hartman | 3e7736e | 2014-09-21 17:34:28 -0700 | [diff] [blame] | 224 | kmem_cache_destroy(gbuf_head_cache); |
Greg Kroah-Hartman | 80e04f0 | 2014-09-13 18:20:54 -0700 | [diff] [blame] | 225 | } |