[patch 18/32] greybus: raw driver
This driver implements the Greybus raw protocol. Signed-off-by: Greg Kroah-Hartman--- drivers/greybus/raw.c | 381 ++ 1 file changed, 381 insertions(+) --- /dev/null +++ b/drivers/greybus/raw.c @@ -0,0 +1,381 @@ +/* + * Greybus driver for the Raw protocol + * + * Copyright 2015 Google Inc. + * Copyright 2015 Linaro Ltd. + * + * Released under the GPLv2 only. + */ +#include +#include +#include +#include +#include +#include +#include +#include + +#include "greybus.h" + +struct gb_raw { + struct gb_connection *connection; + + struct list_head list; + int list_data; + struct mutex list_lock; + dev_t dev; + struct cdev cdev; + struct device *device; +}; + +struct raw_data { + struct list_head entry; + u32 len; + u8 data[0]; +}; + +static struct class *raw_class; +static int raw_major; +static const struct file_operations raw_fops; +static DEFINE_IDA(minors); + +/* Number of minor devices this driver supports */ +#define NUM_MINORS 256 + +/* Maximum size of any one send data buffer we support */ +#define MAX_PACKET_SIZE(PAGE_SIZE * 2) + +/* + * Maximum size of the data in the receive buffer we allow before we start to + * drop messages on the floor + */ +#define MAX_DATA_SIZE (MAX_PACKET_SIZE * 8) + +/* + * Add the raw data message to the list of received messages. + */ +static int receive_data(struct gb_raw *raw, u32 len, u8 *data) +{ + struct raw_data *raw_data; + struct device *dev = >connection->bundle->dev; + int retval = 0; + + if (len > MAX_PACKET_SIZE) { + dev_err(dev, "Too big of a data packet, rejected\n"); + return -EINVAL; + } + + mutex_lock(>list_lock); + if ((raw->list_data + len) > MAX_DATA_SIZE) { + dev_err(dev, "Too much data in receive buffer, now dropping packets\n"); + retval = -EINVAL; + goto exit; + } + + raw_data = kmalloc(sizeof(*raw_data) + len, GFP_KERNEL); + if (!raw_data) { + retval = -ENOMEM; + goto exit; + } + + raw->list_data += len; + raw_data->len = len; + memcpy(_data->data[0], data, len); + + list_add_tail(_data->entry, >list); +exit: + mutex_unlock(>list_lock); + return retval; +} + +static int gb_raw_request_handler(struct gb_operation *op) +{ + struct gb_connection *connection = op->connection; + struct device *dev = >bundle->dev; + struct gb_raw *raw = greybus_get_drvdata(connection->bundle); + struct gb_raw_send_request *receive; + u32 len; + + if (op->type != GB_RAW_TYPE_SEND) { + dev_err(dev, "unknown request type 0x%02x\n", op->type); + return -EINVAL; + } + + /* Verify size of payload */ + if (op->request->payload_size < sizeof(*receive)) { + dev_err(dev, "raw receive request too small (%zu < %zu)\n", + op->request->payload_size, sizeof(*receive)); + return -EINVAL; + } + receive = op->request->payload; + len = le32_to_cpu(receive->len); + if (len != (int)(op->request->payload_size - sizeof(__le32))) { + dev_err(dev, "raw receive request wrong size %d vs %d\n", len, + (int)(op->request->payload_size - sizeof(__le32))); + return -EINVAL; + } + if (len == 0) { + dev_err(dev, "raw receive request of 0 bytes?\n"); + return -EINVAL; + } + + return receive_data(raw, len, receive->data); +} + +static int gb_raw_send(struct gb_raw *raw, u32 len, const char __user *data) +{ + struct gb_connection *connection = raw->connection; + struct gb_raw_send_request *request; + int retval; + + request = kmalloc(len + sizeof(*request), GFP_KERNEL); + if (!request) + return -ENOMEM; + + if (copy_from_user(>data[0], data, len)) { + kfree(request); + return -EFAULT; + } + + request->len = cpu_to_le32(len); + + retval = gb_operation_sync(connection, GB_RAW_TYPE_SEND, + request, len + sizeof(*request), + NULL, 0); + + kfree(request); + return retval; +} + +static int gb_raw_probe(struct gb_bundle *bundle, + const struct greybus_bundle_id *id) +{ + struct greybus_descriptor_cport *cport_desc; + struct gb_connection *connection; + struct gb_raw *raw; + int retval; + int minor; + + if (bundle->num_cports != 1) + return -ENODEV; + + cport_desc = >cport_desc[0]; + if (cport_desc->protocol_id != GREYBUS_PROTOCOL_RAW) + return -ENODEV; + + raw = kzalloc(sizeof(*raw), GFP_KERNEL); + if (!raw) +
[patch 18/32] greybus: raw driver
This driver implements the Greybus raw protocol. Signed-off-by: Greg Kroah-Hartman --- drivers/greybus/raw.c | 381 ++ 1 file changed, 381 insertions(+) --- /dev/null +++ b/drivers/greybus/raw.c @@ -0,0 +1,381 @@ +/* + * Greybus driver for the Raw protocol + * + * Copyright 2015 Google Inc. + * Copyright 2015 Linaro Ltd. + * + * Released under the GPLv2 only. + */ +#include +#include +#include +#include +#include +#include +#include +#include + +#include "greybus.h" + +struct gb_raw { + struct gb_connection *connection; + + struct list_head list; + int list_data; + struct mutex list_lock; + dev_t dev; + struct cdev cdev; + struct device *device; +}; + +struct raw_data { + struct list_head entry; + u32 len; + u8 data[0]; +}; + +static struct class *raw_class; +static int raw_major; +static const struct file_operations raw_fops; +static DEFINE_IDA(minors); + +/* Number of minor devices this driver supports */ +#define NUM_MINORS 256 + +/* Maximum size of any one send data buffer we support */ +#define MAX_PACKET_SIZE(PAGE_SIZE * 2) + +/* + * Maximum size of the data in the receive buffer we allow before we start to + * drop messages on the floor + */ +#define MAX_DATA_SIZE (MAX_PACKET_SIZE * 8) + +/* + * Add the raw data message to the list of received messages. + */ +static int receive_data(struct gb_raw *raw, u32 len, u8 *data) +{ + struct raw_data *raw_data; + struct device *dev = >connection->bundle->dev; + int retval = 0; + + if (len > MAX_PACKET_SIZE) { + dev_err(dev, "Too big of a data packet, rejected\n"); + return -EINVAL; + } + + mutex_lock(>list_lock); + if ((raw->list_data + len) > MAX_DATA_SIZE) { + dev_err(dev, "Too much data in receive buffer, now dropping packets\n"); + retval = -EINVAL; + goto exit; + } + + raw_data = kmalloc(sizeof(*raw_data) + len, GFP_KERNEL); + if (!raw_data) { + retval = -ENOMEM; + goto exit; + } + + raw->list_data += len; + raw_data->len = len; + memcpy(_data->data[0], data, len); + + list_add_tail(_data->entry, >list); +exit: + mutex_unlock(>list_lock); + return retval; +} + +static int gb_raw_request_handler(struct gb_operation *op) +{ + struct gb_connection *connection = op->connection; + struct device *dev = >bundle->dev; + struct gb_raw *raw = greybus_get_drvdata(connection->bundle); + struct gb_raw_send_request *receive; + u32 len; + + if (op->type != GB_RAW_TYPE_SEND) { + dev_err(dev, "unknown request type 0x%02x\n", op->type); + return -EINVAL; + } + + /* Verify size of payload */ + if (op->request->payload_size < sizeof(*receive)) { + dev_err(dev, "raw receive request too small (%zu < %zu)\n", + op->request->payload_size, sizeof(*receive)); + return -EINVAL; + } + receive = op->request->payload; + len = le32_to_cpu(receive->len); + if (len != (int)(op->request->payload_size - sizeof(__le32))) { + dev_err(dev, "raw receive request wrong size %d vs %d\n", len, + (int)(op->request->payload_size - sizeof(__le32))); + return -EINVAL; + } + if (len == 0) { + dev_err(dev, "raw receive request of 0 bytes?\n"); + return -EINVAL; + } + + return receive_data(raw, len, receive->data); +} + +static int gb_raw_send(struct gb_raw *raw, u32 len, const char __user *data) +{ + struct gb_connection *connection = raw->connection; + struct gb_raw_send_request *request; + int retval; + + request = kmalloc(len + sizeof(*request), GFP_KERNEL); + if (!request) + return -ENOMEM; + + if (copy_from_user(>data[0], data, len)) { + kfree(request); + return -EFAULT; + } + + request->len = cpu_to_le32(len); + + retval = gb_operation_sync(connection, GB_RAW_TYPE_SEND, + request, len + sizeof(*request), + NULL, 0); + + kfree(request); + return retval; +} + +static int gb_raw_probe(struct gb_bundle *bundle, + const struct greybus_bundle_id *id) +{ + struct greybus_descriptor_cport *cport_desc; + struct gb_connection *connection; + struct gb_raw *raw; + int retval; + int minor; + + if (bundle->num_cports != 1) + return -ENODEV; + + cport_desc = >cport_desc[0]; + if (cport_desc->protocol_id != GREYBUS_PROTOCOL_RAW) + return -ENODEV; + + raw = kzalloc(sizeof(*raw), GFP_KERNEL); + if (!raw) + return -ENOMEM; + +