cregit-Linux how code gets into the kernel

Release 4.11 drivers/input/serio/hp_sdc.c

/*
 * HP i8042-based System Device Controller driver.
 *
 * Copyright (c) 2001 Brian S. Julin
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL").
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 *
 * References:
 * System Device Controller Microprocessor Firmware Theory of Operation
 *      for Part Number 1820-4784 Revision B.  Dwg No. A-1820-4784-2
 * Helge Deller's original hilkbd.c port for PA-RISC.
 *
 *
 * Driver theory of operation:
 *
 * hp_sdc_put does all writing to the SDC.  ISR can run on a different
 * CPU than hp_sdc_put, but only one CPU runs hp_sdc_put at a time
 * (it cannot really benefit from SMP anyway.)  A tasket fit this perfectly.
 *
 * All data coming back from the SDC is sent via interrupt and can be read
 * fully in the ISR, so there are no latency/throughput problems there.
 * The problem is with output, due to the slow clock speed of the SDC
 * compared to the CPU.  This should not be too horrible most of the time,
 * but if used with HIL devices that support the multibyte transfer command,
 * keeping outbound throughput flowing at the 6500KBps that the HIL is
 * capable of is more than can be done at HZ=100.
 *
 * Busy polling for IBF clear wastes CPU cycles and bus cycles.  hp_sdc.ibf
 * is set to 0 when the IBF flag in the status register has cleared.  ISR
 * may do this, and may also access the parts of queued transactions related
 * to reading data back from the SDC, but otherwise will not touch the
 * hp_sdc state. Whenever a register is written hp_sdc.ibf is set to 1.
 *
 * The i8042 write index and the values in the 4-byte input buffer
 * starting at 0x70 are kept track of in hp_sdc.wi, and .r7[], respectively,
 * to minimize the amount of IO needed to the SDC.  However these values
 * do not need to be locked since they are only ever accessed by hp_sdc_put.
 *
 * A timer task schedules the tasklet once per second just to make
 * sure it doesn't freeze up and to allow for bad reads to time out.
 */

#include <linux/hp_sdc.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/time.h>
#include <linux/semaphore.h>
#include <linux/slab.h>
#include <linux/hil.h>
#include <asm/io.h>

/* Machine-specific abstraction */

#if defined(__hppa__)
# include <asm/parisc-device.h>

# define sdc_readb(p)		gsc_readb(p)

# define sdc_writeb(v,p)	gsc_writeb((v),(p))
#elif defined(__mc68000__)
#include <linux/uaccess.h>

# define sdc_readb(p)		in_8(p)

# define sdc_writeb(v,p)	out_8((p),(v))
#else
# error "HIL is not supported on this platform"
#endif


#define PREFIX "HP SDC: "

MODULE_AUTHOR("Brian S. Julin <bri@calyx.com>");
MODULE_DESCRIPTION("HP i8042-based SDC Driver");
MODULE_LICENSE("Dual BSD/GPL");


EXPORT_SYMBOL(hp_sdc_request_timer_irq);

EXPORT_SYMBOL(hp_sdc_request_hil_irq);

EXPORT_SYMBOL(hp_sdc_request_cooked_irq);


EXPORT_SYMBOL(hp_sdc_release_timer_irq);

EXPORT_SYMBOL(hp_sdc_release_hil_irq);

EXPORT_SYMBOL(hp_sdc_release_cooked_irq);


EXPORT_SYMBOL(__hp_sdc_enqueue_transaction);

EXPORT_SYMBOL(hp_sdc_enqueue_transaction);

EXPORT_SYMBOL(hp_sdc_dequeue_transaction);


static bool hp_sdc_disabled;
module_param_named(no_hpsdc, hp_sdc_disabled, bool, 0);
MODULE_PARM_DESC(no_hpsdc, "Do not enable HP SDC driver.");


static hp_i8042_sdc	hp_sdc;	
/* All driver state is kept in here. */

/*************** primitives for use in any context *********************/

static inline uint8_t hp_sdc_status_in8(void) { uint8_t status; unsigned long flags; write_lock_irqsave(&hp_sdc.ibf_lock, flags); status = sdc_readb(hp_sdc.status_io); if (!(status & HP_SDC_STATUS_IBF)) hp_sdc.ibf = 0; write_unlock_irqrestore(&hp_sdc.ibf_lock, flags); return status; }

Contributors

PersonTokensPropCommitsCommitProp
Helge Deller63100.00%1100.00%
Total63100.00%1100.00%


static inline uint8_t hp_sdc_data_in8(void) { return sdc_readb(hp_sdc.data_io); }

Contributors

PersonTokensPropCommitsCommitProp
Helge Deller17100.00%1100.00%
Total17100.00%1100.00%


static inline void hp_sdc_status_out8(uint8_t val) { unsigned long flags; write_lock_irqsave(&hp_sdc.ibf_lock, flags); hp_sdc.ibf = 1; if ((val & 0xf0) == 0xe0) hp_sdc.wi = 0xff; sdc_writeb(val, hp_sdc.status_io); write_unlock_irqrestore(&hp_sdc.ibf_lock, flags); }

Contributors

PersonTokensPropCommitsCommitProp
Helge Deller65100.00%1100.00%
Total65100.00%1100.00%


static inline void hp_sdc_data_out8(uint8_t val) { unsigned long flags; write_lock_irqsave(&hp_sdc.ibf_lock, flags); hp_sdc.ibf = 1; sdc_writeb(val, hp_sdc.data_io); write_unlock_irqrestore(&hp_sdc.ibf_lock, flags); }

Contributors

PersonTokensPropCommitsCommitProp
Helge Deller49100.00%1100.00%
Total49100.00%1100.00%

/* Care must be taken to only invoke hp_sdc_spin_ibf when * absolutely needed, or in rarely invoked subroutines. * Not only does it waste CPU cycles, it also wastes bus cycles. */
static inline void hp_sdc_spin_ibf(void) { unsigned long flags; rwlock_t *lock; lock = &hp_sdc.ibf_lock; read_lock_irqsave(lock, flags); if (!hp_sdc.ibf) { read_unlock_irqrestore(lock, flags); return; } read_unlock(lock); write_lock(lock); while (sdc_readb(hp_sdc.status_io) & HP_SDC_STATUS_IBF) { } hp_sdc.ibf = 0; write_unlock_irqrestore(lock, flags); }

Contributors

PersonTokensPropCommitsCommitProp
Helge Deller83100.00%2100.00%
Total83100.00%2100.00%

/************************ Interrupt context functions ************************/
static void hp_sdc_take(int irq, void *dev_id, uint8_t status, uint8_t data) { hp_sdc_transaction *curr; read_lock(&hp_sdc.rtq_lock); if (hp_sdc.rcurr < 0) { read_unlock(&hp_sdc.rtq_lock); return; } curr = hp_sdc.tq[hp_sdc.rcurr]; read_unlock(&hp_sdc.rtq_lock); curr->seq[curr->idx++] = status; curr->seq[curr->idx++] = data; hp_sdc.rqty -= 2; do_gettimeofday(&hp_sdc.rtv); if (hp_sdc.rqty <= 0) { /* All data has been gathered. */ if (curr->seq[curr->actidx] & HP_SDC_ACT_SEMAPHORE) if (curr->act.semaphore) up(curr->act.semaphore); if (curr->seq[curr->actidx] & HP_SDC_ACT_CALLBACK) if (curr->act.irqhook) curr->act.irqhook(irq, dev_id, status, data); curr->actidx = curr->idx; curr->idx++; /* Return control of this transaction */ write_lock(&hp_sdc.rtq_lock); hp_sdc.rcurr = -1; hp_sdc.rqty = 0; write_unlock(&hp_sdc.rtq_lock); tasklet_schedule(&hp_sdc.task); } }

Contributors

PersonTokensPropCommitsCommitProp
Helge Deller235100.00%1100.00%
Total235100.00%1100.00%


static irqreturn_t hp_sdc_isr(int irq, void *dev_id) { uint8_t status, data; status = hp_sdc_status_in8(); /* Read data unconditionally to advance i8042. */ data = hp_sdc_data_in8(); /* For now we are ignoring these until we get the SDC to behave. */ if (((status & 0xf1) == 0x51) && data == 0x82) return IRQ_HANDLED; switch (status & HP_SDC_STATUS_IRQMASK) { case 0: /* This case is not documented. */ break; case HP_SDC_STATUS_USERTIMER: case HP_SDC_STATUS_PERIODIC: case HP_SDC_STATUS_TIMER: read_lock(&hp_sdc.hook_lock); if (hp_sdc.timer != NULL) hp_sdc.timer(irq, dev_id, status, data); read_unlock(&hp_sdc.hook_lock); break; case HP_SDC_STATUS_REG: hp_sdc_take(irq, dev_id, status, data); break; case HP_SDC_STATUS_HILCMD: case HP_SDC_STATUS_HILDATA: read_lock(&hp_sdc.hook_lock); if (hp_sdc.hil != NULL) hp_sdc.hil(irq, dev_id, status, data); read_unlock(&hp_sdc.hook_lock); break; case HP_SDC_STATUS_PUP: read_lock(&hp_sdc.hook_lock); if (hp_sdc.pup != NULL) hp_sdc.pup(irq, dev_id, status, data); else printk(KERN_INFO PREFIX "HP SDC reports successful PUP.\n"); read_unlock(&hp_sdc.hook_lock); break; default: read_lock(&hp_sdc.hook_lock); if (hp_sdc.cooked != NULL) hp_sdc.cooked(irq, dev_id, status, data); read_unlock(&hp_sdc.hook_lock); break; } return IRQ_HANDLED; }

Contributors

PersonTokensPropCommitsCommitProp
Helge Deller258100.00%1100.00%
Total258100.00%1100.00%


static irqreturn_t hp_sdc_nmisr(int irq, void *dev_id) { int status; status = hp_sdc_status_in8(); printk(KERN_WARNING PREFIX "NMI !\n"); #if 0 if (status & HP_SDC_NMISTATUS_FHS) { read_lock(&hp_sdc.hook_lock); if (hp_sdc.timer != NULL) hp_sdc.timer(irq, dev_id, status, 0); read_unlock(&hp_sdc.hook_lock); } else { /* TODO: pass this on to the HIL handler, or do SAK here? */ printk(KERN_WARNING PREFIX "HIL NMI\n"); } #endif return IRQ_HANDLED; }

Contributors

PersonTokensPropCommitsCommitProp
Helge Deller38100.00%2100.00%
Total38100.00%2100.00%

/***************** Kernel (tasklet) context functions ****************/ unsigned long hp_sdc_put(void);
static void hp_sdc_tasklet(unsigned long foo) { write_lock_irq(&hp_sdc.rtq_lock); if (hp_sdc.rcurr >= 0) { struct timeval tv; do_gettimeofday(&tv); if (tv.tv_sec > hp_sdc.rtv.tv_sec) tv.tv_usec += USEC_PER_SEC; if (tv.tv_usec - hp_sdc.rtv.tv_usec > HP_SDC_MAX_REG_DELAY) { hp_sdc_transaction *curr; uint8_t tmp; curr = hp_sdc.tq[hp_sdc.rcurr]; /* If this turns out to be a normal failure mode * we'll need to figure out a way to communicate * it back to the application. and be less verbose. */ printk(KERN_WARNING PREFIX "read timeout (%ius)!\n", (int)(tv.tv_usec - hp_sdc.rtv.tv_usec)); curr->idx += hp_sdc.rqty; hp_sdc.rqty = 0; tmp = curr->seq[curr->actidx]; curr->seq[curr->actidx] |= HP_SDC_ACT_DEAD; if (tmp & HP_SDC_ACT_SEMAPHORE) if (curr->act.semaphore) up(curr->act.semaphore); if (tmp & HP_SDC_ACT_CALLBACK) { /* Note this means that irqhooks may be called * in tasklet/bh context. */ if (curr->act.irqhook) curr->act.irqhook(0, NULL, 0, 0); } curr->actidx = curr->idx; curr->idx++; hp_sdc.rcurr = -1; } } write_unlock_irq(&hp_sdc.rtq_lock); hp_sdc_put(); }

Contributors

PersonTokensPropCommitsCommitProp
Helge Deller21999.10%250.00%
Geert Uytterhoeven10.45%125.00%
Al Viro10.45%125.00%
Total221100.00%4100.00%


unsigned long hp_sdc_put(void) { hp_sdc_transaction *curr; uint8_t act; int idx, curridx; int limit = 0; write_lock(&hp_sdc.lock); /* If i8042 buffers are full, we cannot do anything that requires output, so we skip to the administrativa. */ if (hp_sdc.ibf) { hp_sdc_status_in8(); if (hp_sdc.ibf) goto finish; } anew: /* See if we are in the middle of a sequence. */ if (hp_sdc.wcurr < 0) hp_sdc.wcurr = 0; read_lock_irq(&hp_sdc.rtq_lock); if (hp_sdc.rcurr == hp_sdc.wcurr) hp_sdc.wcurr++; read_unlock_irq(&hp_sdc.rtq_lock); if (hp_sdc.wcurr >= HP_SDC_QUEUE_LEN) hp_sdc.wcurr = 0; curridx = hp_sdc.wcurr; if (hp_sdc.tq[curridx] != NULL) goto start; while (++curridx != hp_sdc.wcurr) { if (curridx >= HP_SDC_QUEUE_LEN) { curridx = -1; /* Wrap to top */ continue; } read_lock_irq(&hp_sdc.rtq_lock); if (hp_sdc.rcurr == curridx) { read_unlock_irq(&hp_sdc.rtq_lock); continue; } read_unlock_irq(&hp_sdc.rtq_lock); if (hp_sdc.tq[curridx] != NULL) break; /* Found one. */ } if (curridx == hp_sdc.wcurr) { /* There's nothing queued to do. */ curridx = -1; } hp_sdc.wcurr = curridx; start: /* Check to see if the interrupt mask needs to be set. */ if (hp_sdc.set_im) { hp_sdc_status_out8(hp_sdc.im | HP_SDC_CMD_SET_IM); hp_sdc.set_im = 0; goto finish; } if (hp_sdc.wcurr == -1) goto done; curr = hp_sdc.tq[curridx]; idx = curr->actidx; if (curr->actidx >= curr->endidx) { hp_sdc.tq[curridx] = NULL; /* Interleave outbound data between the transactions. */ hp_sdc.wcurr++; if (hp_sdc.wcurr >= HP_SDC_QUEUE_LEN) hp_sdc.wcurr = 0; goto finish; } act = curr->seq[idx]; idx++; if (curr->idx >= curr->endidx) { if (act & HP_SDC_ACT_DEALLOC) kfree(curr); hp_sdc.tq[curridx] = NULL; /* Interleave outbound data between the transactions. */ hp_sdc.wcurr++; if (hp_sdc.wcurr >= HP_SDC_QUEUE_LEN) hp_sdc.wcurr = 0; goto finish; } while (act & HP_SDC_ACT_PRECMD) { if (curr->idx != idx) { idx++; act &= ~HP_SDC_ACT_PRECMD; break; } hp_sdc_status_out8(curr->seq[idx]); curr->idx++; /* act finished? */ if ((act & HP_SDC_ACT_DURING) == HP_SDC_ACT_PRECMD) goto actdone; /* skip quantity field if data-out sequence follows. */ if (act & HP_SDC_ACT_DATAOUT) curr->idx++; goto finish; } if (act & HP_SDC_ACT_DATAOUT) { int qty; qty = curr->seq[idx]; idx++; if (curr->idx - idx < qty) { hp_sdc_data_out8(curr->seq[curr->idx]); curr->idx++; /* act finished? */ if (curr->idx - idx >= qty && (act & HP_SDC_ACT_DURING) == HP_SDC_ACT_DATAOUT) goto actdone; goto finish; } idx += qty; act &= ~HP_SDC_ACT_DATAOUT; } else while (act & HP_SDC_ACT_DATAREG) { int mask; uint8_t w7[4]; mask = curr->seq[idx]; if (idx != curr->idx) { idx++; idx += !!(mask & 1); idx += !!(mask & 2); idx += !!(mask & 4); idx += !!(mask & 8); act &= ~HP_SDC_ACT_DATAREG; break; } w7[0] = (mask & 1) ? curr->seq[++idx] : hp_sdc.r7[0]; w7[1] = (mask & 2) ? curr->seq[++idx] : hp_sdc.r7[1]; w7[2] = (mask & 4) ? curr->seq[++idx] : hp_sdc.r7[2]; w7[3] = (mask & 8) ? curr->seq[++idx] : hp_sdc.r7[3]; if (hp_sdc.wi > 0x73 || hp_sdc.wi < 0x70 || w7[hp_sdc.wi - 0x70] == hp_sdc.r7[hp_sdc.wi - 0x70]) { int i = 0; /* Need to point the write index register */ while (i < 4 && w7[i] == hp_sdc.r7[i]) i++; if (i < 4) { hp_sdc_status_out8(HP_SDC_CMD_SET_D0 + i); hp_sdc.wi = 0x70 + i; goto finish; } idx++; if ((act & HP_SDC_ACT_DURING) == HP_SDC_ACT_DATAREG) goto actdone; curr->idx = idx; act &= ~HP_SDC_ACT_DATAREG; break; } hp_sdc_data_out8(w7[hp_sdc.wi - 0x70]); hp_sdc.r7[hp_sdc.wi - 0x70] = w7[hp_sdc.wi - 0x70]; hp_sdc.wi++; /* write index register autoincrements */ { int i = 0; while ((i < 4) && w7[i] == hp_sdc.r7[i]) i++; if (i >= 4) { curr->idx = idx + 1; if ((act & HP_SDC_ACT_DURING) == HP_SDC_ACT_DATAREG) goto actdone; } } goto finish; } /* We don't go any further in the command if there is a pending read, because we don't want interleaved results. */ read_lock_irq(&hp_sdc.rtq_lock); if (hp_sdc.rcurr >= 0) { read_unlock_irq(&hp_sdc.rtq_lock); goto finish; } read_unlock_irq(&hp_sdc.rtq_lock); if (act & HP_SDC_ACT_POSTCMD) { uint8_t postcmd; /* curr->idx should == idx at this point. */ postcmd = curr->seq[idx]; curr->idx++; if (act & HP_SDC_ACT_DATAIN) { /* Start a new read */ hp_sdc.rqty = curr->seq[curr->idx]; do_gettimeofday(&hp_sdc.rtv); curr->idx++; /* Still need to lock here in case of spurious irq. */ write_lock_irq(&hp_sdc.rtq_lock); hp_sdc.rcurr = curridx; write_unlock_irq(&hp_sdc.rtq_lock); hp_sdc_status_out8(postcmd); goto finish; } hp_sdc_status_out8(postcmd); goto actdone; } actdone: if (act & HP_SDC_ACT_SEMAPHORE) up(curr->act.semaphore); else if (act & HP_SDC_ACT_CALLBACK) curr->act.irqhook(0,NULL,0,0); if (curr->idx >= curr->endidx) { /* This transaction is over. */ if (act & HP_SDC_ACT_DEALLOC) kfree(curr); hp_sdc.tq[curridx] = NULL; } else { curr->actidx = idx + 1; curr->idx = idx + 2; } /* Interleave outbound data between the transactions. */ hp_sdc.wcurr++; if (hp_sdc.wcurr >= HP_SDC_QUEUE_LEN) hp_sdc.wcurr = 0; finish: /* If by some quirk IBF has cleared and our ISR has run to see that that has happened, do it all again. */ if (!hp_sdc.ibf && limit++ < 20) goto anew; done: if (hp_sdc.wcurr >= 0) tasklet_schedule(&hp_sdc.task); write_unlock(&hp_sdc.lock); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Helge Deller125899.92%266.67%
Al Viro10.08%133.33%
Total1259100.00%3100.00%

/******* Functions called in either user or kernel context ****/
int __hp_sdc_enqueue_transaction(hp_sdc_transaction *this) { int i; if (this == NULL) { BUG(); return -EINVAL; } /* Can't have same transaction on queue twice */ for (i = 0; i < HP_SDC_QUEUE_LEN; i++) if (hp_sdc.tq[i] == this) goto fail; this->actidx = 0; this->idx = 1; /* Search for empty slot */ for (i = 0; i < HP_SDC_QUEUE_LEN; i++) if (hp_sdc.tq[i] == NULL) { hp_sdc.tq[i] = this; tasklet_schedule(&hp_sdc.task); return 0; } printk(KERN_WARNING PREFIX "No free slot to add transaction.\n"); return -EBUSY; fail: printk(KERN_WARNING PREFIX "Transaction add failed: transaction already queued?\n"); return -EINVAL; }

Contributors

PersonTokensPropCommitsCommitProp
Helge Deller136100.00%2100.00%
Total136100.00%2100.00%


int hp_sdc_enqueue_transaction(hp_sdc_transaction *this) { unsigned long flags; int ret; write_lock_irqsave(&hp_sdc.lock, flags); ret = __hp_sdc_enqueue_transaction(this); write_unlock_irqrestore(&hp_sdc.lock,flags); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Helge Deller46100.00%2100.00%
Total46100.00%2100.00%


int hp_sdc_dequeue_transaction(hp_sdc_transaction *this) { unsigned long flags; int i; write_lock_irqsave(&hp_sdc.lock, flags); /* TODO: don't remove it if it's not done. */ for (i = 0; i < HP_SDC_QUEUE_LEN; i++) if (hp_sdc.tq[i] == this) hp_sdc.tq[i] = NULL; write_unlock_irqrestore(&hp_sdc.lock, flags); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Helge Deller73100.00%1100.00%
Total73100.00%1100.00%

/********************** User context functions **************************/
int hp_sdc_request_timer_irq(hp_sdc_irqhook *callback) { if (callback == NULL || hp_sdc.dev == NULL) return -EINVAL; write_lock_irq(&hp_sdc.hook_lock); if (hp_sdc.timer != NULL) { write_unlock_irq(&hp_sdc.hook_lock); return -EBUSY; } hp_sdc.timer = callback; /* Enable interrupts from the timers */ hp_sdc.im &= ~HP_SDC_IM_FH; hp_sdc.im &= ~HP_SDC_IM_PT; hp_sdc.im &= ~HP_SDC_IM_TIMERS; hp_sdc.set_im = 1; write_unlock_irq(&hp_sdc.hook_lock); tasklet_schedule(&hp_sdc.task); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Helge Deller108100.00%1100.00%
Total108100.00%1100.00%


int hp_sdc_request_hil_irq(hp_sdc_irqhook *callback) { if (callback == NULL || hp_sdc.dev == NULL) return -EINVAL; write_lock_irq(&hp_sdc.hook_lock); if (hp_sdc.hil != NULL) { write_unlock_irq(&hp_sdc.hook_lock); return -EBUSY; } hp_sdc.hil = callback; hp_sdc.im &= ~(HP_SDC_IM_HIL | HP_SDC_IM_RESET); hp_sdc.set_im = 1; write_unlock_irq(&hp_sdc.hook_lock); tasklet_schedule(&hp_sdc.task); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Helge Deller97100.00%1100.00%
Total97100.00%1100.00%


int hp_sdc_request_cooked_irq(hp_sdc_irqhook *callback) { if (callback == NULL || hp_sdc.dev == NULL) return -EINVAL; write_lock_irq(&hp_sdc.hook_lock); if (hp_sdc.cooked != NULL) { write_unlock_irq(&hp_sdc.hook_lock); return -EBUSY; } /* Enable interrupts from the HIL MLC */ hp_sdc.cooked = callback; hp_sdc.im