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authorLinus Torvalds <torvalds@linux-foundation.org>2010-05-20 21:26:12 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-05-20 21:26:12 -0700
commit7a9b149212f3716c598afe973b6261fd58453b7a (patch)
tree477716d84c71da124448b72278e98da28aadbd3d /Documentation/usb
parent3d62e3fdce8ef265a3706c52ae1ca6ab84e30f0e (diff)
parente26bcf37234c67624f62d9fc95f922b8dbda1363 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (229 commits) USB: remove unused usb_buffer_alloc and usb_buffer_free macros usb: musb: update gfp/slab.h includes USB: ftdi_sio: fix legacy SIO-device header USB: kl5usb105: reimplement using generic framework USB: kl5usb105: minor clean ups USB: kl5usb105: fix memory leak USB: io_ti: use kfifo to implement write buffering USB: io_ti: remove unsused private counter USB: ti_usb: use kfifo to implement write buffering USB: ir-usb: fix incorrect write-buffer length USB: aircable: fix incorrect write-buffer length USB: safe_serial: straighten out read processing USB: safe_serial: reimplement read using generic framework USB: safe_serial: reimplement write using generic framework usb-storage: always print quirks USB: usb-storage: trivial debug improvements USB: oti6858: use port write fifo USB: oti6858: use kfifo to implement write buffering USB: cypress_m8: use kfifo to implement write buffering USB: cypress_m8: remove unused drain define ... Fix up conflicts (due to usb_buffer_alloc/free renaming) in drivers/input/tablet/acecad.c drivers/input/tablet/kbtab.c drivers/input/tablet/wacom_sys.c drivers/media/video/gspca/gspca.c sound/usb/usbaudio.c
Diffstat (limited to 'Documentation/usb')
-rw-r--r--Documentation/usb/bulk-streams.txt78
-rw-r--r--Documentation/usb/dma.txt22
-rw-r--r--Documentation/usb/gadget_hid.txt445
-rw-r--r--Documentation/usb/power-management.txt19
-rw-r--r--Documentation/usb/usb-serial.txt29
5 files changed, 567 insertions, 26 deletions
diff --git a/Documentation/usb/bulk-streams.txt b/Documentation/usb/bulk-streams.txt
new file mode 100644
index 00000000000..ffc02021863
--- /dev/null
+++ b/Documentation/usb/bulk-streams.txt
@@ -0,0 +1,78 @@
+Background
+==========
+
+Bulk endpoint streams were added in the USB 3.0 specification. Streams allow a
+device driver to overload a bulk endpoint so that multiple transfers can be
+queued at once.
+
+Streams are defined in sections 4.4.6.4 and 8.12.1.4 of the Universal Serial Bus
+3.0 specification at http://www.usb.org/developers/docs/ The USB Attached SCSI
+Protocol, which uses streams to queue multiple SCSI commands, can be found on
+the T10 website (http://t10.org/).
+
+
+Device-side implications
+========================
+
+Once a buffer has been queued to a stream ring, the device is notified (through
+an out-of-band mechanism on another endpoint) that data is ready for that stream
+ID. The device then tells the host which "stream" it wants to start. The host
+can also initiate a transfer on a stream without the device asking, but the
+device can refuse that transfer. Devices can switch between streams at any
+time.
+
+
+Driver implications
+===================
+
+int usb_alloc_streams(struct usb_interface *interface,
+ struct usb_host_endpoint **eps, unsigned int num_eps,
+ unsigned int num_streams, gfp_t mem_flags);
+
+Device drivers will call this API to request that the host controller driver
+allocate memory so the driver can use up to num_streams stream IDs. They must
+pass an array of usb_host_endpoints that need to be setup with similar stream
+IDs. This is to ensure that a UASP driver will be able to use the same stream
+ID for the bulk IN and OUT endpoints used in a Bi-directional command sequence.
+
+The return value is an error condition (if one of the endpoints doesn't support
+streams, or the xHCI driver ran out of memory), or the number of streams the
+host controller allocated for this endpoint. The xHCI host controller hardware
+declares how many stream IDs it can support, and each bulk endpoint on a
+SuperSpeed device will say how many stream IDs it can handle. Therefore,
+drivers should be able to deal with being allocated less stream IDs than they
+requested.
+
+Do NOT call this function if you have URBs enqueued for any of the endpoints
+passed in as arguments. Do not call this function to request less than two
+streams.
+
+Drivers will only be allowed to call this API once for the same endpoint
+without calling usb_free_streams(). This is a simplification for the xHCI host
+controller driver, and may change in the future.
+
+
+Picking new Stream IDs to use
+============================
+
+Stream ID 0 is reserved, and should not be used to communicate with devices. If
+usb_alloc_streams() returns with a value of N, you may use streams 1 though N.
+To queue an URB for a specific stream, set the urb->stream_id value. If the
+endpoint does not support streams, an error will be returned.
+
+Note that new API to choose the next stream ID will have to be added if the xHCI
+driver supports secondary stream IDs.
+
+
+Clean up
+========
+
+If a driver wishes to stop using streams to communicate with the device, it
+should call
+
+void usb_free_streams(struct usb_interface *interface,
+ struct usb_host_endpoint **eps, unsigned int num_eps,
+ gfp_t mem_flags);
+
+All stream IDs will be deallocated when the driver releases the interface, to
+ensure that drivers that don't support streams will be able to use the endpoint.
diff --git a/Documentation/usb/dma.txt b/Documentation/usb/dma.txt
index cfdcd16e3ab..84ef865237d 100644
--- a/Documentation/usb/dma.txt
+++ b/Documentation/usb/dma.txt
@@ -16,11 +16,11 @@ OR: they can now be DMA-aware.
manage dma mappings for existing dma-ready buffers (see below).
- URBs have an additional "transfer_dma" field, as well as a transfer_flags
- bit saying if it's valid. (Control requests also have "setup_dma" and a
- corresponding transfer_flags bit.)
+ bit saying if it's valid. (Control requests also have "setup_dma", but
+ drivers must not use it.)
-- "usbcore" will map those DMA addresses, if a DMA-aware driver didn't do
- it first and set URB_NO_TRANSFER_DMA_MAP or URB_NO_SETUP_DMA_MAP. HCDs
+- "usbcore" will map this DMA address, if a DMA-aware driver didn't do
+ it first and set URB_NO_TRANSFER_DMA_MAP. HCDs
don't manage dma mappings for URBs.
- There's a new "generic DMA API", parts of which are usable by USB device
@@ -43,22 +43,16 @@ and effects like cache-trashing can impose subtle penalties.
kind of addresses to store in urb->transfer_buffer and urb->transfer_dma.
You'd also set URB_NO_TRANSFER_DMA_MAP in urb->transfer_flags:
- void *usb_buffer_alloc (struct usb_device *dev, size_t size,
+ void *usb_alloc_coherent (struct usb_device *dev, size_t size,
int mem_flags, dma_addr_t *dma);
- void usb_buffer_free (struct usb_device *dev, size_t size,
+ void usb_free_coherent (struct usb_device *dev, size_t size,
void *addr, dma_addr_t dma);
Most drivers should *NOT* be using these primitives; they don't need
to use this type of memory ("dma-coherent"), and memory returned from
kmalloc() will work just fine.
- For control transfers you can use the buffer primitives or not for each
- of the transfer buffer and setup buffer independently. Set the flag bits
- URB_NO_TRANSFER_DMA_MAP and URB_NO_SETUP_DMA_MAP to indicate which
- buffers you have prepared. For non-control transfers URB_NO_SETUP_DMA_MAP
- is ignored.
-
The memory buffer returned is "dma-coherent"; sometimes you might need to
force a consistent memory access ordering by using memory barriers. It's
not using a streaming DMA mapping, so it's good for small transfers on
@@ -130,8 +124,8 @@ of Documentation/PCI/PCI-DMA-mapping.txt, titled "What memory is DMA-able?")
void usb_buffer_unmap (struct urb *urb);
The calls manage urb->transfer_dma for you, and set URB_NO_TRANSFER_DMA_MAP
- so that usbcore won't map or unmap the buffer. The same goes for
- urb->setup_dma and URB_NO_SETUP_DMA_MAP for control requests.
+ so that usbcore won't map or unmap the buffer. They cannot be used for
+ setup_packet buffers in control requests.
Note that several of those interfaces are currently commented out, since
they don't have current users. See the source code. Other than the dmasync
diff --git a/Documentation/usb/gadget_hid.txt b/Documentation/usb/gadget_hid.txt
new file mode 100644
index 00000000000..f4a51f56742
--- /dev/null
+++ b/Documentation/usb/gadget_hid.txt
@@ -0,0 +1,445 @@
+
+ Linux USB HID gadget driver
+
+Introduction
+
+ The HID Gadget driver provides emulation of USB Human Interface
+ Devices (HID). The basic HID handling is done in the kernel,
+ and HID reports can be sent/received through I/O on the
+ /dev/hidgX character devices.
+
+ For more details about HID, see the developer page on
+ http://www.usb.org/developers/hidpage/
+
+Configuration
+
+ g_hid is a platform driver, so to use it you need to add
+ struct platform_device(s) to your platform code defining the
+ HID function descriptors you want to use - E.G. something
+ like:
+
+#include <linux/platform_device.h>
+#include <linux/usb/g_hid.h>
+
+/* hid descriptor for a keyboard */
+static struct hidg_func_descriptor my_hid_data = {
+ .subclass = 0, /* No subclass */
+ .protocol = 1, /* Keyboard */
+ .report_length = 8,
+ .report_desc_length = 63,
+ .report_desc = {
+ 0x05, 0x01, /* USAGE_PAGE (Generic Desktop) */
+ 0x09, 0x06, /* USAGE (Keyboard) */
+ 0xa1, 0x01, /* COLLECTION (Application) */
+ 0x05, 0x07, /* USAGE_PAGE (Keyboard) */
+ 0x19, 0xe0, /* USAGE_MINIMUM (Keyboard LeftControl) */
+ 0x29, 0xe7, /* USAGE_MAXIMUM (Keyboard Right GUI) */
+ 0x15, 0x00, /* LOGICAL_MINIMUM (0) */
+ 0x25, 0x01, /* LOGICAL_MAXIMUM (1) */
+ 0x75, 0x01, /* REPORT_SIZE (1) */
+ 0x95, 0x08, /* REPORT_COUNT (8) */
+ 0x81, 0x02, /* INPUT (Data,Var,Abs) */
+ 0x95, 0x01, /* REPORT_COUNT (1) */
+ 0x75, 0x08, /* REPORT_SIZE (8) */
+ 0x81, 0x03, /* INPUT (Cnst,Var,Abs) */
+ 0x95, 0x05, /* REPORT_COUNT (5) */
+ 0x75, 0x01, /* REPORT_SIZE (1) */
+ 0x05, 0x08, /* USAGE_PAGE (LEDs) */
+ 0x19, 0x01, /* USAGE_MINIMUM (Num Lock) */
+ 0x29, 0x05, /* USAGE_MAXIMUM (Kana) */
+ 0x91, 0x02, /* OUTPUT (Data,Var,Abs) */
+ 0x95, 0x01, /* REPORT_COUNT (1) */
+ 0x75, 0x03, /* REPORT_SIZE (3) */
+ 0x91, 0x03, /* OUTPUT (Cnst,Var,Abs) */
+ 0x95, 0x06, /* REPORT_COUNT (6) */
+ 0x75, 0x08, /* REPORT_SIZE (8) */
+ 0x15, 0x00, /* LOGICAL_MINIMUM (0) */
+ 0x25, 0x65, /* LOGICAL_MAXIMUM (101) */
+ 0x05, 0x07, /* USAGE_PAGE (Keyboard) */
+ 0x19, 0x00, /* USAGE_MINIMUM (Reserved) */
+ 0x29, 0x65, /* USAGE_MAXIMUM (Keyboard Application) */
+ 0x81, 0x00, /* INPUT (Data,Ary,Abs) */
+ 0xc0 /* END_COLLECTION */
+ }
+};
+
+static struct platform_device my_hid = {
+ .name = "hidg",
+ .id = 0,
+ .num_resources = 0,
+ .resource = 0,
+ .dev.platform_data = &my_hid_data,
+};
+
+ You can add as many HID functions as you want, only limited by
+ the amount of interrupt endpoints your gadget driver supports.
+
+Send and receive HID reports
+
+ HID reports can be sent/received using read/write on the
+ /dev/hidgX character devices. See below for an example program
+ to do this.
+
+ hid_gadget_test is a small interactive program to test the HID
+ gadget driver. To use, point it at a hidg device and set the
+ device type (keyboard / mouse / joystick) - E.G.:
+
+ # hid_gadget_test /dev/hidg0 keyboard
+
+ You are now in the prompt of hid_gadget_test. You can type any
+ combination of options and values. Available options and
+ values are listed at program start. In keyboard mode you can
+ send up to six values.
+
+ For example type: g i s t r --left-shift
+
+ Hit return and the corresponding report will be sent by the
+ HID gadget.
+
+ Another interesting example is the caps lock test. Type
+ -–caps-lock and hit return. A report is then sent by the
+ gadget and you should receive the host answer, corresponding
+ to the caps lock LED status.
+
+ --caps-lock
+ recv report:2
+
+ With this command:
+
+ # hid_gadget_test /dev/hidg1 mouse
+
+ You can test the mouse emulation. Values are two signed numbers.
+
+
+Sample code
+
+/* hid_gadget_test */
+
+#include <pthread.h>
+#include <string.h>
+#include <stdio.h>
+#include <ctype.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#define BUF_LEN 512
+
+struct options {
+ const char *opt;
+ unsigned char val;
+};
+
+static struct options kmod[] = {
+ {.opt = "--left-ctrl", .val = 0x01},
+ {.opt = "--right-ctrl", .val = 0x10},
+ {.opt = "--left-shift", .val = 0x02},
+ {.opt = "--right-shift", .val = 0x20},
+ {.opt = "--left-alt", .val = 0x04},
+ {.opt = "--right-alt", .val = 0x40},
+ {.opt = "--left-meta", .val = 0x08},
+ {.opt = "--right-meta", .val = 0x80},
+ {.opt = NULL}
+};
+
+static struct options kval[] = {
+ {.opt = "--return", .val = 0x28},
+ {.opt = "--esc", .val = 0x29},
+ {.opt = "--bckspc", .val = 0x2a},
+ {.opt = "--tab", .val = 0x2b},
+ {.opt = "--spacebar", .val = 0x2c},
+ {.opt = "--caps-lock", .val = 0x39},
+ {.opt = "--f1", .val = 0x3a},
+ {.opt = "--f2", .val = 0x3b},
+ {.opt = "--f3", .val = 0x3c},
+ {.opt = "--f4", .val = 0x3d},
+ {.opt = "--f5", .val = 0x3e},
+ {.opt = "--f6", .val = 0x3f},
+ {.opt = "--f7", .val = 0x40},
+ {.opt = "--f8", .val = 0x41},
+ {.opt = "--f9", .val = 0x42},
+ {.opt = "--f10", .val = 0x43},
+ {.opt = "--f11", .val = 0x44},
+ {.opt = "--f12", .val = 0x45},
+ {.opt = "--insert", .val = 0x49},
+ {.opt = "--home", .val = 0x4a},
+ {.opt = "--pageup", .val = 0x4b},
+ {.opt = "--del", .val = 0x4c},
+ {.opt = "--end", .val = 0x4d},
+ {.opt = "--pagedown", .val = 0x4e},
+ {.opt = "--right", .val = 0x4f},
+ {.opt = "--left", .val = 0x50},
+ {.opt = "--down", .val = 0x51},
+ {.opt = "--kp-enter", .val = 0x58},
+ {.opt = "--up", .val = 0x52},
+ {.opt = "--num-lock", .val = 0x53},
+ {.opt = NULL}
+};
+
+int keyboard_fill_report(char report[8], char buf[BUF_LEN], int *hold)
+{
+ char *tok = strtok(buf, " ");
+ int key = 0;
+ int i = 0;
+
+ for (; tok != NULL; tok = strtok(NULL, " ")) {
+
+ if (strcmp(tok, "--quit") == 0)
+ return -1;
+
+ if (strcmp(tok, "--hold") == 0) {
+ *hold = 1;
+ continue;
+ }
+
+ if (key < 6) {
+ for (i = 0; kval[i].opt != NULL; i++)
+ if (strcmp(tok, kval[i].opt) == 0) {
+ report[2 + key++] = kval[i].val;
+ break;
+ }
+ if (kval[i].opt != NULL)
+ continue;
+ }
+
+ if (key < 6)
+ if (islower(tok[0])) {
+ report[2 + key++] = (tok[0] - ('a' - 0x04));
+ continue;
+ }
+
+ for (i = 0; kmod[i].opt != NULL; i++)
+ if (strcmp(tok, kmod[i].opt) == 0) {
+ report[0] = report[0] | kmod[i].val;
+ break;
+ }
+ if (kmod[i].opt != NULL)
+ continue;
+
+ if (key < 6)
+ fprintf(stderr, "unknown option: %s\n", tok);
+ }
+ return 8;
+}
+
+static struct options mmod[] = {
+ {.opt = "--b1", .val = 0x01},
+ {.opt = "--b2", .val = 0x02},
+ {.opt = "--b3", .val = 0x04},
+ {.opt = NULL}
+};
+
+int mouse_fill_report(char report[8], char buf[BUF_LEN], int *hold)
+{
+ char *tok = strtok(buf, " ");
+ int mvt = 0;
+ int i = 0;
+ for (; tok != NULL; tok = strtok(NULL, " ")) {
+
+ if (strcmp(tok, "--quit") == 0)
+ return -1;
+
+ if (strcmp(tok, "--hold") == 0) {
+ *hold = 1;
+ continue;
+ }
+
+ for (i = 0; mmod[i].opt != NULL; i++)
+ if (strcmp(tok, mmod[i].opt) == 0) {
+ report[0] = report[0] | mmod[i].val;
+ break;
+ }
+ if (mmod[i].opt != NULL)
+ continue;
+
+ if (!(tok[0] == '-' && tok[1] == '-') && mvt < 2) {
+ errno = 0;
+ report[1 + mvt++] = (char)strtol(tok, NULL, 0);
+ if (errno != 0) {
+ fprintf(stderr, "Bad value:'%s'\n", tok);
+ report[1 + mvt--] = 0;
+ }
+ continue;
+ }
+
+ fprintf(stderr, "unknown option: %s\n", tok);
+ }
+ return 3;
+}
+
+static struct options jmod[] = {
+ {.opt = "--b1", .val = 0x10},
+ {.opt = "--b2", .val = 0x20},
+ {.opt = "--b3", .val = 0x40},
+ {.opt = "--b4", .val = 0x80},
+ {.opt = "--hat1", .val = 0x00},
+ {.opt = "--hat2", .val = 0x01},
+ {.opt = "--hat3", .val = 0x02},
+ {.opt = "--hat4", .val = 0x03},
+ {.opt = "--hatneutral", .val = 0x04},
+ {.opt = NULL}
+};
+
+int joystick_fill_report(char report[8], char buf[BUF_LEN], int *hold)
+{
+ char *tok = strtok(buf, " ");
+ int mvt = 0;
+ int i = 0;
+
+ *hold = 1;
+
+ /* set default hat position: neutral */
+ report[3] = 0x04;
+
+ for (; tok != NULL; tok = strtok(NULL, " ")) {
+
+ if (strcmp(tok, "--quit") == 0)
+ return -1;
+
+ for (i = 0; jmod[i].opt != NULL; i++)
+ if (strcmp(tok, jmod[i].opt) == 0) {
+ report[3] = (report[3] & 0xF0) | jmod[i].val;
+ break;
+ }
+ if (jmod[i].opt != NULL)
+ continue;
+
+ if (!(tok[0] == '-' && tok[1] == '-') && mvt < 3) {
+ errno = 0;
+ report[mvt++] = (char)strtol(tok, NULL, 0);
+ if (errno != 0) {
+ fprintf(stderr, "Bad value:'%s'\n", tok);
+ report[mvt--] = 0;
+ }
+ continue;
+ }
+
+ fprintf(stderr, "unknown option: %s\n", tok);
+ }
+ return 4;
+}
+
+void print_options(char c)
+{
+ int i = 0;
+
+ if (c == 'k') {
+ printf(" keyboard options:\n"
+ " --hold\n");
+ for (i = 0; kmod[i].opt != NULL; i++)
+ printf("\t\t%s\n", kmod[i].opt);
+ printf("\n keyboard values:\n"
+ " [a-z] or\n");
+ for (i = 0; kval[i].opt != NULL; i++)
+ printf("\t\t%-8s%s", kval[i].opt, i % 2 ? "\n" : "");
+ printf("\n");
+ } else if (c == 'm') {
+ printf(" mouse options:\n"
+ " --hold\n");
+ for (i = 0; mmod[i].opt != NULL; i++)
+ printf("\t\t%s\n", mmod[i].opt);
+ printf("\n mouse values:\n"
+ " Two signed numbers\n"
+ "--quit to close\n");
+ } else {
+ printf(" joystick options:\n");
+ for (i = 0; jmod[i].opt != NULL; i++)
+ printf("\t\t%s\n", jmod[i].opt);
+ printf("\n joystick values:\n"
+ " three signed numbers\n"
+ "--quit to close\n");
+ }
+}
+
+int main(int argc, const char *argv[])
+{
+ const char *filename = NULL;
+ int fd = 0;
+ char buf[BUF_LEN];
+ int cmd_len;
+ char report[8];
+ int to_send = 8;
+ int hold = 0;
+ fd_set rfds;
+ int retval, i;
+
+ if (argc < 3) {
+ fprintf(stderr, "Usage: %s devname mouse|keyboard|joystick\n",
+ argv[0]);
+ return 1;
+ }
+
+ if (argv[2][0] != 'k' && argv[2][0] != 'm' && argv[2][0] != 'j')
+ return 2;
+
+ filename = argv[1];
+
+ if ((fd = open(filename, O_RDWR, 0666)) == -1) {
+ perror(filename);
+ return 3;
+ }
+
+ print_options(argv[2][0]);
+
+ while (42) {
+
+ FD_ZERO(&rfds);
+ FD_SET(STDIN_FILENO, &rfds);
+ FD_SET(fd, &rfds);
+
+ retval = select(fd + 1, &rfds, NULL, NULL, NULL);
+ if (retval == -1 && errno == EINTR)
+ continue;
+ if (retval < 0) {
+ perror("select()");
+ return 4;
+ }
+
+ if (FD_ISSET(fd, &rfds)) {
+ cmd_len = read(fd, buf, BUF_LEN - 1);
+ printf("recv report:");
+ for (i = 0; i < cmd_len; i++)
+ printf(" %02x", buf[i]);
+ printf("\n");
+ }
+
+ if (FD_ISSET(STDIN_FILENO, &rfds)) {
+ memset(report, 0x0, sizeof(report));
+ cmd_len = read(STDIN_FILENO, buf, BUF_LEN - 1);
+
+ if (cmd_len == 0)
+ break;
+
+ buf[cmd_len - 1] = '\0';
+ hold = 0;
+
+ memset(report, 0x0, sizeof(report));
+ if (argv[2][0] == 'k')
+ to_send = keyboard_fill_report(report, buf, &hold);
+ else if (argv[2][0] == 'm')
+ to_send = mouse_fill_report(report, buf, &hold);
+ else
+ to_send = joystick_fill_report(report, buf, &hold);
+
+ if (to_send == -1)
+ break;
+
+ if (write(fd, report, to_send) != to_send) {
+ perror(filename);
+ return 5;
+ }
+ if (!hold) {
+ memset(report, 0x0, sizeof(report));
+ if (write(fd, report, to_send) != to_send) {
+ perror(filename);
+ return 6;
+ }
+ }
+ }
+ }
+
+ close(fd);
+ return 0;
+}
diff --git a/Documentation/usb/power-management.txt b/Documentation/usb/power-management.txt
index 2790ad48cfc..b29d8e56cf2 100644
--- a/Documentation/usb/power-management.txt
+++ b/Documentation/usb/power-management.txt
@@ -107,7 +107,9 @@ allowed to issue dynamic suspends.
The user interface for controlling dynamic PM is located in the power/
subdirectory of each USB device's sysfs directory, that is, in
/sys/bus/usb/devices/.../power/ where "..." is the device's ID. The
-relevant attribute files are: wakeup, level, and autosuspend.
+relevant attribute files are: wakeup, control, and autosuspend.
+(There may also be a file named "level"; this file was deprecated
+as of the 2.6.35 kernel and replaced by the "control" file.)
power/wakeup
@@ -120,7 +122,7 @@ relevant attribute files are: wakeup, level, and autosuspend.
while the device is suspended, the change won't take
effect until the following suspend.)
- power/level
+ power/control
This file contains one of two words: "on" or "auto".
You can write those words to the file to change the
@@ -148,14 +150,15 @@ relevant attribute files are: wakeup, level, and autosuspend.
never to autosuspend. You can write a number to the
file to change the autosuspend idle-delay time.
-Writing "-1" to power/autosuspend and writing "on" to power/level do
+Writing "-1" to power/autosuspend and writing "on" to power/control do
essentially the same thing -- they both prevent the device from being
autosuspended. Yes, this is a redundancy in the API.
(In 2.6.21 writing "0" to power/autosuspend would prevent the device
from being autosuspended; the behavior was changed in 2.6.22. The
power/autosuspend attribute did not exist prior to 2.6.21, and the
-power/level attribute did not exist prior to 2.6.22.)
+power/level attribute did not exist prior to 2.6.22. power/control
+was added in 2.6.34.)
Changing the default idle-delay time
@@ -212,7 +215,7 @@ among printers and scanners, but plenty of other types of device have
the same deficiency.
For this reason, by default the kernel disables autosuspend (the
-power/level attribute is initialized to "on") for all devices other
+power/control attribute is initialized to "on") for all devices other
than hubs. Hubs, at least, appear to be reasonably well-behaved in
this regard.
@@ -373,7 +376,7 @@ usb_autopm_put_interface() in its close or release routine. But other
patterns are possible.
The autosuspend attempts mentioned above will often fail for one
-reason or another. For example, the power/level attribute might be
+reason or another. For example, the power/control attribute might be
set to "on", or another interface in the same device might not be
idle. This is perfectly normal. If the reason for failure was that
the device hasn't been idle for long enough, a timer is scheduled to
@@ -394,12 +397,12 @@ Drivers can enable autosuspend for their devices by calling
in their probe() routine, if they know that the device is capable of
suspending and resuming correctly. This is exactly equivalent to
-writing "auto" to the device's power/level attribute. Likewise,
+writing "auto" to the device's power/control attribute. Likewise,
drivers can disable autosuspend by calling
usb_disable_autosuspend(struct usb_device *udev);
-This is exactly the same as writing "on" to the power/level attribute.
+This is exactly the same as writing "on" to the power/control attribute.
Sometimes a driver needs to make sure that remote wakeup is enabled
during autosuspend. For example, there's not much point
diff --git a/Documentation/usb/usb-serial.txt b/Documentation/usb/usb-serial.txt
index ff2c1ff57ba..f4d21451025 100644
--- a/Documentation/usb/usb-serial.txt
+++ b/Documentation/usb/usb-serial.txt
@@ -194,6 +194,10 @@ FTDI Single Port Serial Driver
This is a single port DB-25 serial adapter.
+ Devices supported include:
+ -TripNav TN-200 USB GPS
+ -Navis Engineering Bureau CH-4711 USB GPS
+
For any questions or problems with this driver, please contact Bill Ryder.
@@ -216,7 +220,7 @@ Cypress M8 CY4601 Family Serial Driver
Devices supported:
- -DeLorme's USB Earthmate (SiRF Star II lp arch)
+ -DeLorme's USB Earthmate GPS (SiRF Star II lp arch)
-Cypress HID->COM RS232 adapter
Note: Cypress Semiconductor claims no affiliation with the
@@ -392,9 +396,10 @@ REINER SCT cyberJack pinpad/e-com USB chipcard reader
Prolific PL2303 Driver
This driver supports any device that has the PL2303 chip from Prolific
- in it. This includes a number of single port USB to serial
- converters and USB GPS devices. Devices from Aten (the UC-232) and
- IO-Data work with this driver, as does the DCU-11 mobile-phone cable.
+ in it. This includes a number of single port USB to serial converters,
+ more than 70% of USB GPS devices (in 2010), and some USB UPSes. Devices
+ from Aten (the UC-232) and IO-Data work with this driver, as does
+ the DCU-11 mobile-phone cable.
For any questions or problems with this driver, please contact Greg
Kroah-Hartman at greg@kroah.com
@@ -435,6 +440,22 @@ Winchiphead CH341 Driver
For any questions or problems with this driver, please contact
frank@kingswood-consulting.co.uk.
+Moschip MCS7720, MCS7715 driver
+
+ These chips are present in devices sold by various manufacturers, such as Syba
+ and Cables Unlimited. There may be others. The 7720 provides two serial
+ ports, and the 7715 provides one serial and one standard PC parallel port.
+ Support for the 7715's parallel port is enabled by a separate option, which
+ will not appear unless parallel port support is first enabled at the top-level
+ of the Device Drivers config menu. Currently only compatibility mode is
+ supported on the parallel port (no ECP/EPP).
+
+ TODO:
+ - Implement ECP/EPP modes for the parallel port.
+ - Baud rates higher than 115200 are currently broken.
+ - Devices with a single serial port based on the Moschip MCS7703 may work
+ with this driver with a simple addition to the usb_device_id table. I
+ don't have one of these devices, so I can't say for sure.
Generic Serial driver