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|
/*
* A driver for the Griffin Technology, Inc. "PowerMate" USB controller dial.
*
* v1.1, (c)2002 William R Sowerbutts <will@sowerbutts.com>
*
* This device is a anodised aluminium knob which connects over USB. It can measure
* clockwise and anticlockwise rotation. The dial also acts as a pushbutton with
* a spring for automatic release. The base contains a pair of LEDs which illuminate
* the translucent base. It rotates without limit and reports its relative rotation
* back to the host when polled by the USB controller.
*
* Testing with the knob I have has shown that it measures approximately 94 "clicks"
* for one full rotation. Testing with my High Speed Rotation Actuator (ok, it was
* a variable speed cordless electric drill) has shown that the device can measure
* speeds of up to 7 clicks either clockwise or anticlockwise between pollings from
* the host. If it counts more than 7 clicks before it is polled, it will wrap back
* to zero and start counting again. This was at quite high speed, however, almost
* certainly faster than the human hand could turn it. Griffin say that it loses a
* pulse or two on a direction change; the granularity is so fine that I never
* noticed this in practice.
*
* The device's microcontroller can be programmed to set the LED to either a constant
* intensity, or to a rhythmic pulsing. Several patterns and speeds are available.
*
* Griffin were very happy to provide documentation and free hardware for development.
*
* Some userspace tools are available on the web: http://sowerbutts.com/powermate/
*
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/usb/input.h>
#define POWERMATE_VENDOR 0x077d /* Griffin Technology, Inc. */
#define POWERMATE_PRODUCT_NEW 0x0410 /* Griffin PowerMate */
#define POWERMATE_PRODUCT_OLD 0x04AA /* Griffin soundKnob */
#define CONTOUR_VENDOR 0x05f3 /* Contour Design, Inc. */
#define CONTOUR_JOG 0x0240 /* Jog and Shuttle */
/* these are the command codes we send to the device */
#define SET_STATIC_BRIGHTNESS 0x01
#define SET_PULSE_ASLEEP 0x02
#define SET_PULSE_AWAKE 0x03
#define SET_PULSE_MODE 0x04
/* these refer to bits in the powermate_device's requires_update field. */
#define UPDATE_STATIC_BRIGHTNESS (1<<0)
#define UPDATE_PULSE_ASLEEP (1<<1)
#define UPDATE_PULSE_AWAKE (1<<2)
#define UPDATE_PULSE_MODE (1<<3)
/* at least two versions of the hardware exist, with differing payload
sizes. the first three bytes always contain the "interesting" data in
the relevant format. */
#define POWERMATE_PAYLOAD_SIZE_MAX 6
#define POWERMATE_PAYLOAD_SIZE_MIN 3
struct powermate_device {
signed char *data;
dma_addr_t data_dma;
struct urb *irq, *config;
struct usb_ctrlrequest *configcr;
struct usb_device *udev;
struct usb_interface *intf;
struct input_dev *input;
spinlock_t lock;
int static_brightness;
int pulse_speed;
int pulse_table;
int pulse_asleep;
int pulse_awake;
int requires_update; // physical settings which are out of sync
char phys[64];
};
static char pm_name_powermate[] = "Griffin PowerMate";
static char pm_name_soundknob[] = "Griffin SoundKnob";
static void powermate_config_complete(struct urb *urb);
/* Callback for data arriving from the PowerMate over the USB interrupt pipe */
static void powermate_irq(struct urb *urb)
{
struct powermate_device *pm = urb->context;
struct device *dev = &pm->intf->dev;
int retval;
switch (urb->status) {
case 0:
/* success */
break;
case -ECONNRESET:
case -ENOENT:
case -ESHUTDOWN:
/* this urb is terminated, clean up */
dev_dbg(dev, "%s - urb shutting down with status: %d\n",
__func__, urb->status);
return;
default:
dev_dbg(dev, "%s - nonzero urb status received: %d\n",
__func__, urb->status);
goto exit;
}
/* handle updates to device state */
input_report_key(pm->input, BTN_0, pm->data[0] & 0x01);
input_report_rel(pm->input, REL_DIAL, pm->data[1]);
input_sync(pm->input);
exit:
retval = usb_submit_urb (urb, GFP_ATOMIC);
if (retval)
dev_err(dev, "%s - usb_submit_urb failed with result: %d\n",
__func__, retval);
}
/* Decide if we need to issue a control message and do so. Must be called with pm->lock taken */
static void powermate_sync_state(struct powermate_device *pm)
{
if (pm->requires_update == 0)
return; /* no updates are required */
if (pm->config->status == -EINPROGRESS)
return; /* an update is already in progress; it'll issue this update when it completes */
if (pm->requires_update & UPDATE_PULSE_ASLEEP){
pm->configcr->wValue = cpu_to_le16( SET_PULSE_ASLEEP );
pm->configcr->wIndex = cpu_to_le16( pm->pulse_asleep ? 1 : 0 );
pm->requires_update &= ~UPDATE_PULSE_ASLEEP;
}else if (pm->requires_update & UPDATE_PULSE_AWAKE){
pm->configcr->wValue = cpu_to_le16( SET_PULSE_AWAKE );
pm->configcr->wIndex = cpu_to_le16( pm->pulse_awake ? 1 : 0 );
pm->requires_update &= ~UPDATE_PULSE_AWAKE;
}else if (pm->requires_update & UPDATE_PULSE_MODE){
int op, arg;
/* the powermate takes an operation and an argument for its pulse algorithm.
the operation can be:
0: divide the speed
1: pulse at normal speed
2: multiply the speed
the argument only has an effect for operations 0 and 2, and ranges between
1 (least effect) to 255 (maximum effect).
thus, several states are equivalent and are coalesced into one state.
we map this onto a range from 0 to 510, with:
0 -- 254 -- use divide (0 = slowest)
255 -- use normal speed
256 -- 510 -- use multiple (510 = fastest).
Only values of 'arg' quite close to 255 are particularly useful/spectacular.
*/
if (pm->pulse_speed < 255) {
op = 0; // divide
arg = 255 - pm->pulse_speed;
} else if (pm->pulse_speed > 255) {
op = 2; // multiply
arg = pm->pulse_speed - 255;
} else {
op = 1; // normal speed
arg = 0; // can be any value
}
pm->configcr->wValue = cpu_to_le16( (pm->pulse_table << 8) | SET_PULSE_MODE );
pm->configcr->wIndex = cpu_to_le16( (arg << 8) | op );
pm->requires_update &= ~UPDATE_PULSE_MODE;
} else if (pm->requires_update & UPDATE_STATIC_BRIGHTNESS) {
pm->configcr->wValue = cpu_to_le16( SET_STATIC_BRIGHTNESS );
pm->configcr->wIndex = cpu_to_le16( pm->static_brightness );
pm->requires_update &= ~UPDATE_STATIC_BRIGHTNESS;
} else {
printk(KERN_ERR "powermate: unknown update required");
pm->requires_update = 0; /* fudge the bug */
return;
}
/* printk("powermate: %04x %04x\n", pm->configcr->wValue, pm->configcr->wIndex); */
pm->configcr->bRequestType = 0x41; /* vendor request */
pm->configcr->bRequest = 0x01;
pm->configcr->wLength = 0;
usb_fill_control_urb(pm->config, pm->udev, usb_sndctrlpipe(pm->udev, 0),
(void *) pm->configcr, NULL, 0,
powermate_config_complete, pm);
if (usb_submit_urb(pm->config, GFP_ATOMIC))
printk(KERN_ERR "powermate: usb_submit_urb(config) failed");
}
/* Called when our asynchronous control message completes. We may need to issue another immediately */
static void powermate_config_complete(struct urb *urb)
{
struct powermate_device *pm = urb->context;
unsigned long flags;
if (urb->status)
printk(KERN_ERR "powermate: config urb returned %d\n", urb->status);
spin_lock_irqsave(&pm->lock, flags);
powermate_sync_state(pm);
spin_unlock_irqrestore(&pm->lock, flags);
}
/* Set the LED up as described and begin the sync with the hardware if required */
static void powermate_pulse_led(struct powermate_device *pm, int static_brightness, int pulse_speed,
int pulse_table, int pulse_asleep, int pulse_awake)
{
unsigned long flags;
if (pulse_speed < 0)
pulse_speed = 0;
if (pulse_table < 0)
pulse_table = 0;
if (pulse_speed > 510)
pulse_speed = 510;
if (pulse_table > 2)
pulse_table = 2;
pulse_asleep = !!pulse_asleep;
pulse_awake = !!pulse_awake;
spin_lock_irqsave(&pm->lock, flags);
/* mark state updates which are required */
if (static_brightness != pm->static_brightness) {
pm->static_brightness = static_brightness;
pm->requires_update |= UPDATE_STATIC_BRIGHTNESS;
}
if (pulse_asleep != pm->pulse_asleep) {
pm->pulse_asleep = pulse_asleep;
pm->requires_update |= (UPDATE_PULSE_ASLEEP | UPDATE_STATIC_BRIGHTNESS);
}
if (pulse_awake != pm->pulse_awake) {
pm->pulse_awake = pulse_awake;
pm->requires_update |= (UPDATE_PULSE_AWAKE | UPDATE_STATIC_BRIGHTNESS);
}
if (pulse_speed != pm->pulse_speed || pulse_table != pm->pulse_table) {
pm->pulse_speed = pulse_speed;
pm->pulse_table = pulse_table;
pm->requires_u
|