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/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * NXP TDA18218HN silicon tuner driver
 *
 * Copyright (C) 2010 Antti Palosaari <crope@iki.fi>
 */

#ifndef TDA18218_PRIV_H
#define TDA18218_PRIV_H

#include "tda18218.h"

#define R00_ID         0x00	/* ID byte */
#define R01_R1         0x01	/* Read byte 1 */
#define R02_R2         0x02	/* Read byte 2 */
#define R03_R3         0x03	/* Read byte 3 */
#define R04_R4         0x04	/* Read byte 4 */
#define R05_R5         0x05	/* Read byte 5 */
#define R06_R6         0x06	/* Read byte 6 */
#define R07_MD1        0x07	/* Main divider byte 1 */
#define R08_PSM1       0x08	/* PSM byte 1 */
#define R09_MD2        0x09	/* Main divider byte 2 */
#define R0A_MD3        0x0a	/* Main divider byte 1 */
#define R0B_MD4        0x0b	/* Main divider byte 4 */
#define R0C_MD5        0x0c	/* Main divider byte 5 */
#define R0D_MD6        0x0d	/* Main divider byte 6 */
#define R0E_MD7        0x0e	/* Main divider byte 7 */
#define R0F_MD8        0x0f	/* Main divider byte 8 */
#define R10_CD1        0x10	/* Call divider byte 1 */
#define R11_CD2        0x11	/* Call divider byte 2 */
#define R12_CD3        0x12	/* Call divider byte 3 */
#define R13_CD4        0x13	/* Call divider byte 4 */
#define R14_CD5        0x14	/* Call divider byte 5 */
#define R15_CD6        0x15	/* Call divider byte 6 */
#define R16_CD7        0x16	/* Call divider byte 7 */
#define R17_PD1        0x17	/* Power-down byte 1 */
#define R18_PD2        0x18	/* Power-down byte 2 */
#define R19_XTOUT      0x19	/* XTOUT byte */
#define R1A_IF1        0x1a	/* IF byte 1 */
#define R1B_IF2        0x1b	/* IF byte 2 */
#define R1C_AGC2B      0x1c	/* AGC2b byte */
#define R1D_PSM2       0x1d	/* PSM byte 2 */
#define R1E_PSM3       0x1e	/* PSM byte 3 */
#define R1F_PSM4       0x1f	/* PSM byte 4 */
#define R20_AGC11      0x20	/* AGC1 byte 1 */
#define R21_AGC12      0x21	/* AGC1 byte 2 */
#define R22_AGC13      0x22	/* AGC1 byte 3 */
#define R23_AGC21      0x23	/* AGC2 byte 1 */
#define R24_AGC22      0x24	/* AGC2 byte 2 */
#define R25_AAGC       0x25	/* Analog AGC byte */
#define R26_RC         0x26	/* RC byte */
#define R27_RSSI       0x27	/* RSSI byte */
#define R28_IRCAL1     0x28	/* IR CAL byte 1 */
#define R29_IRCAL2     0x29	/* IR CAL byte 2 */
#define R2A_IRCAL3     0x2a	/* IR CAL byte 3 */
#define R2B_IRCAL4     0x2b	/* IR CAL byte 4 */
#define R2C_RFCAL1     0x2c	/* RF CAL byte 1 */
#define R2D_RFCAL2     0x2d	/* RF CAL byte 2 */
#define R2E_RFCAL3     0x2e	/* RF CAL byte 3 */
#define R2F_RFCAL4     0x2f	/* RF CAL byte 4 */
#define R30_RFCAL5     0x30	/* RF CAL byte 5 */
#define R31_RFCAL6     0x31	/* RF CAL byte 6 */
#define R32_RFCAL7     0x32	/* RF CAL byte 7 */
#define R33_RFCAL8     0x33	/* RF CAL byte 8 */
#define R34_RFCAL9     0x34	/* RF CAL byte 9 */
#define R35_RFCAL10    0x35	/* RF CAL byte 10 */
#define R36_RFCALRAM1  0x36	/* RF CAL RAM byte 1 */
#define R37_RFCALRAM2  0x37	/* RF CAL RAM byte 2 */
#define R38_MARGIN     0x38	/* Margin byte */
#define R39_FMAX1      0x39	/* Fmax byte 1 */
#define R3A_FMAX2      0x3a	/* Fmax byte 2 */

#define TDA18218_NUM_REGS 59

struct tda18218_priv {
	struct tda18218_config *cfg;
	struct i2c_adapter *i2c;

	u32 if_frequency;

	u8 regs[TDA18218_NUM_REGS];
};

#endif
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/*
 *  linux/mm/oom_kill.c
 * 
 *  Copyright (C)  1998,2000  Rik van Riel
 *	Thanks go out to Claus Fischer for some serious inspiration and
 *	for goading me into coding this file...
 *
 *  The routines in this file are used to kill a process when
 *  we're seriously out of memory. This gets called from __alloc_pages()
 *  in mm/page_alloc.c when we really run out of memory.
 *
 *  Since we won't call these routines often (on a well-configured
 *  machine) this file will double as a 'coding guide' and a signpost
 *  for newbie kernel hackers. It features several pointers to major
 *  kernel subsystems and hints as to where to find out what things do.
 */

#include <linux/oom.h>
#include <linux/mm.h>
#include <linux/err.h>
#include <linux/sched.h>
#include <linux/swap.h>
#include <linux/timex.h>
#include <linux/jiffies.h>
#include <linux/cpuset.h>
#include <linux/module.h>
#include <linux/notifier.h>

int sysctl_panic_on_oom;
int sysctl_oom_kill_allocating_task;
static DEFINE_SPINLOCK(zone_scan_mutex);
/* #define DEBUG */

/**
 * badness - calculate a numeric value for how bad this task has been
 * @p: task struct of which task we should calculate
 * @uptime: current uptime in seconds
 *
 * The formula used is relatively simple and documented inline in the
 * function. The main rationale is that we want to select a good task
 * to kill when we run out of memory.
 *
 * Good in this context means that:
 * 1) we lose the minimum amount of work done
 * 2) we recover a large amount of memory
 * 3) we don't kill anything innocent of eating tons of memory
 * 4) we want to kill the minimum amount of processes (one)
 * 5) we try to kill the process the user expects us to kill, this
 *    algorithm has been meticulously tuned to meet the principle
 *    of least surprise ... (be careful when you change it)
 */

unsigned long badness(struct task_struct *p, unsigned long uptime)
{
	unsigned long points, cpu_time, run_time, s;
	struct mm_struct *mm;
	struct task_struct *child;

	task_lock(p);
	mm = p->mm;
	if (!mm) {
		task_unlock(p);
		return 0;
	}

	/*
	 * The memory size of the process is the basis for the badness.
	 */
	points = mm->total_vm;

	/*
	 * After this unlock we can no longer dereference local variable `mm'
	 */
	task_unlock(p);

	/*
	 * swapoff can easily use up all memory, so kill those first.
	 */
	if (p->flags & PF_SWAPOFF)
		return ULONG_MAX;

	/*
	 * Processes which fork a lot of child processes are likely
	 * a good choice. We add half the vmsize of the children if they
	 * have an own mm. This prevents forking servers to flood the
	 * machine with an endless amount of children. In case a single
	 * child is eating the vast majority of memory, adding only half
	 * to the parents will make the child our kill candidate of choice.
	 */
	list_for_each_entry(child, &p->children, sibling) {
		task_lock(child);
		if (child->mm != mm && child->mm)
			points += child->mm->total_vm/2 + 1;
		task_unlock(child);
	}

	/*
	 * CPU time is in tens of seconds and run time is in thousands
         * of seconds. There is no particular reason for this other than
         * that it turned out to work very well in practice.
	 */
	cpu_time = (cputime_to_jiffies(p->utime) + cputime_to_jiffies(p->stime))
		>> (SHIFT_HZ + 3);

	if (uptime >= p->start_time.tv_sec)
		run_time = (uptime - p->start_time.tv_sec) >> 10;
	else
		run_time = 0;

	s = int_sqrt(cpu_time);
	if (s)
		points /= s;
	s = int_sqrt(int_sqrt(run_time));
	if (s)
		points /= s;

	/*
	 * Niced processes are most likely less important, so double
	 * their badness points.
	 */
	if (task_nice(p) > 0)
		points *= 2;

	/*
	 * Superuser processes are usually more important, so we make it
	 * less likely that we kill those.
	 */
	if (cap_t(p->cap_effective) & CAP_TO_MASK(CAP_SYS_ADMIN) ||
				p->uid == 0 || p->euid == 0)
		points /= 4;

	/*
	 * We don't want to kill a process with direct hardware access.
	 * Not only could that mess up the hardware, but usually users
	 * tend to only have this flag set on applications they think
	 * of as important.
	 */
	if (cap_t(p->cap_effective) & CAP_TO_MASK(CAP_SYS_RAWIO))
		points /= 4;

	/*
	 * If p's nodes don't overlap ours, it may still help to kill p
	 * because p may have allocated or otherwise mapped memory on
	 * this node before. However it will be less likely.
	 */
	if (!cpuset_mems_allowed_intersects(current, p))
		points /= 8;

	/*
	 * Adjust the score by oomkilladj.
	 */
	if (p->oomkilladj) {
		if (p->oomkilladj > 0) {
			if (!points)
				points = 1;
			points <<= p->oomkilladj;
		} else
			points >>= -(p->oomkilladj);
	}

#ifdef DEBUG
	printk(KERN_DEBUG "OOMkill: task %d (%s) got %lu points\n",
	p->pid, p->comm, points);
#endif
	return points;
}

/*
 * Determine the type of allocation constraint.
 */
static inline enum oom_constraint constrained_alloc(struct zonelist *zonelist,
						    gfp_t gfp_mask)
{
#ifdef CONFIG_NUMA
	struct zone **z;
	nodemask_t nodes = node_states[N_HIGH_MEMORY];

	for (z = zonelist->zones; *z; z++)
		if (cpuset_zone_allowed_softwall(*z, gfp_mask))
			node_clear(zone_to_nid(*z), nodes);
		else
			return CONSTRAINT_CPUSET;

	if (!nodes_empty(nodes))
		return CONSTRAINT_MEMORY_POLICY;
#endif

	return CONSTRAINT_NONE;
}

/*
 * Simple selection loop. We chose the process with the highest
 * number of 'points'. We expect the caller will lock the tasklist.
 *
 * (not docbooked, we don't want this one cluttering up the manual)
 */
static struct task_struct *select_bad_process(unsigned long *ppoints)
{
	struct task_struct *g, *p;
	struct task_struct *chosen = NULL;
	struct timespec uptime;
	*ppoints = 0;

	do_posix_clock_monotonic_gettime(&uptime);
	do_each_thread(g, p) {
		unsigned long points;

		/*
		 * skip kernel threads and tasks which have already released
		 * their mm.
		 */
		if (!p->mm)
			continue;
		/* skip the init task */
		if (is_global_init(p))
			continue;

		/*
		 * This task already has access to memory reserves and is
		 * being killed. Don't allow any other task access to the
		 * memory reserve.
		 *
		 * Note: this may have a chance of deadlock if it gets
		 * blocked waiting for another task which itself is waiting
		 * for memory. Is there a better alternative?
		 */
		if (test_tsk_thread_flag(p, TIF_MEMDIE))
			return ERR_PTR(-1UL);

		/*
		 * This is in the process of releasing memory so wait for it
		 * to finish before killing some other task by mistake.
		 *
		 * However, if p is the current task, we allow the 'kill' to
		 * go ahead if it is exiting: this will simply set TIF_MEMDIE,
		 * which will allow it to gain access to memory reserves in
		 * the process of exiting and releasing its resources.
		 * Otherwise we could get an easy OOM deadlock.
		 */
		if (p->flags & PF_EXITING) {
			if (p != current)
				return ERR_PTR(-1UL);

			chosen = p;
			*ppoints = ULONG_MAX;
		}

		if (p->oomkilladj == OOM_DISABLE)
			continue;

		points = badness(p, uptime.tv_sec);
		if (points > *ppoints || !chosen) {
			chosen = p;
			*ppoints = points;
		}
	} while_each_thread(g, p);

	return chosen;
}

/**
 * Send SIGKILL to the selected  process irrespective of  CAP_SYS_RAW_IO
 * flag though it's unlikely that  we select a process with CAP_SYS_RAW_IO
 * set.
 */
static void __oom_kill_task(struct task_struct *p, int verbose)
{
	if (is_global_init(p)) {
		WARN_ON(1);
		printk(KERN_WARNING "tried to kill init!\n");
		return;
	}

	if (!p->mm) {
		WARN_ON(1);
		printk(KERN_WARNING "tried to kill an mm-less task!\n");
		return;
	}

	if (verbose)
		printk(KERN_ERR "Killed process %d (%s)\n",
				task_pid_nr(p), p->comm);

	/*
	 * We give our sacrificial lamb high priority and access to
	 * all the memory it needs. That way it should be able to
	 * exit() and clear out its resources quickly...
	 */
	p->rt.time_slice = HZ;
	set_tsk_thread_flag(p, TIF_MEMDIE);

	force_sig(SIGKILL, p);
}

static int oom_kill_task(struct task_struct *p)
{
	struct mm_struct *mm;
	struct task_struct *g, *q;

	mm = p->mm;

	/* WARNING: mm may not be dereferenced since we did not obtain its
	 * value from get_task_mm(p).  This is OK since all we need to do is
	 * compare mm to q->mm below.
	 *
	 * Furthermore, even if mm contains a non-NULL value, p->mm may
	 * change to NULL at any time since we do not hold task_lock(p).
	 * However, this is of no concern to us.
	 */

	if (mm == NULL)
		return 1;

	/*
	 * Don't kill the process if any threads are set to OOM_DISABLE
	 */
	do_each_thread(g, q) {
		if (q->mm == mm && q->oomkilladj == OOM_DISABLE)
			return 1;
	} while_each_thread(g, q);

	__oom_kill_task(p, 1);

	/*
	 * kill all processes that share the ->mm (i.e. all threads),
	 * but are in a different thread group. Don't let them have access
	 * to memory reserves though, otherwise we might deplete all memory.
	 */
	do_each_thread(g, q) {
		if (q->mm == mm && !same_thread_group(q, p))
			force_sig(SIGKILL, q);
	} while_each_thread(g, q);

	return 0;
}

static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order,
			    unsigned long points, const char *message)
{
	struct task_struct *c;

	if (printk_ratelimit()) {
		printk(KERN_WARNING "%s invoked oom-killer: "
			"gfp_mask=0x%x, order=%d, oomkilladj=%d\n",
			current->comm, gfp_mask, order, current->oomkilladj);
		dump_stack();
		show_mem();
	}

	/*
	 * If the task is already exiting, don't alarm the sysadmin or kill
	 * its children or threads, just set TIF_MEMDIE so it can die quickly
	 */
	if (p->flags & PF_EXITING) {
		__oom_kill_task(p, 0);
		return 0;
	}

	printk(KERN_ERR "%s: kill process %d (%s) score %li or a child\n",
					message, task_pid_nr(p), p->comm, points);

	/* Try to kill a child first */
	list_for_each_entry(c, &p->children, sibling) {
		if (c->mm == p->mm)
			continue;
		if (!oom_kill_task(c))
			return 0;
	}
	return oom_kill_task(p);
}

static BLOCKING_NOTIFIER_HEAD(oom_notify_list);

int register_oom_notifier(struct notifier_block *nb)
{
	return blocking_notifier_chain_register(&oom_notify_list, nb);
}
EXPORT_SYMBOL_GPL(register_oom_notifier);

int unregister_oom_notifier(struct notifier_block *nb)
{
	return blocking_notifier_chain_unregister(&oom_notify_list, nb);
}
EXPORT_SYMBOL_GPL(unregister_oom_notifier);

/*
 * Try to acquire the OOM killer lock for the zones in zonelist.  Returns zero
 * if a parallel OOM killing is already taking place that includes a zone in
 * the zonelist.  Otherwise, locks all zones in the zonelist and returns 1.
 */
int try_set_zone_oom(struct zonelist *zonelist)
{
	struct zone **z;
	int ret = 1;

	z = zonelist->zones;

	spin_lock(&zone_scan_mutex);
	do {
		if (zone_is_oom_locked(*z)) {
			ret = 0;
			goto out;
		}
	} while (*(++z) != NULL);

	/*
	 * Lock each zone in the zonelist under zone_scan_mutex so a parallel
	 * invocation of try_set_zone_oom() doesn't succeed when it shouldn't.
	 */
	z = zonelist->zones;
	do {
		zone_set_flag(*z, ZONE_OOM_LOCKED);
	} while (*(++z) != NULL);
out:
	spin_unlock(&zone_scan_mutex);
	return ret;
}

/*
 * Clears the ZONE_OOM_LOCKED flag for all zones in the zonelist so that failed
 * allocation attempts with zonelists containing them may now recall the OOM
 * killer, if necessary.
 */
void clear_zonelist_oom(struct zonelist *zonelist)
{
	struct zone **z;

	z = zonelist->zones;

	spin_lock(&zone_scan_mutex);
	do {
		zone_clear_flag(*z, ZONE_OOM_LOCKED);
	} while (*(++z) != NULL);
	spin_unlock(&zone_scan_mutex);
}

/**
 * out_of_memory - kill the "best" process when we run out of memory
 *
 * If we run out of memory, we have the choice between either
 * killing a random task (bad), letting the system crash (worse)
 * OR try to be smart about which process to kill. Note that we
 * don't have to be perfect here, we just have to be good.
 */
void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask, int order)
{
	struct task_struct *p;
	unsigned long points = 0;
	unsigned long freed = 0;
	enum oom_constraint constraint;

	blocking_notifier_call_chain(&oom_notify_list, 0, &freed);
	if (freed > 0)
		/* Got some memory back in the last second. */
		return;

	if (sysctl_panic_on_oom == 2)
		panic("out of memory. Compulsory panic_on_oom is selected.\n");

	/*
	 * Check if there were limitations on the allocation (only relevant for
	 * NUMA) that may require different handling.
	 */
	constraint = constrained_alloc(zonelist, gfp_mask);
	read_lock(&tasklist_lock);

	switch (constraint) {
	case CONSTRAINT_MEMORY_POLICY:
		oom_kill_process(current, gfp_mask, order, points,
				"No available memory (MPOL_BIND)");
		break;

	case CONSTRAINT_NONE:
		if (sysctl_panic_on_oom)
			panic("out of memory. panic_on_oom is selected\n");
		/* Fall-through */
	case CONSTRAINT_CPUSET:
		if (sysctl_oom_kill_allocating_task) {
			oom_kill_process(current, gfp_mask, order, points,
					"Out of memory (oom_kill_allocating_task)");
			break;
		}
retry:
		/*
		 * Rambo mode: Shoot down a process and hope it solves whatever
		 * issues we may have.
		 */
		p = select_bad_process(&points);

		if (PTR_ERR(p) == -1UL)
			goto out;

		/* Found nothing?!?! Either we hang forever, or we panic. */
		if (!p) {
			read_unlock(&tasklist_lock);
			panic("Out of memory and no killable processes...\n");
		}

		if (oom_kill_process(p, gfp_mask, order, points,
				     "Out of memory"))
			goto retry;

		break;
	}

out:
	read_unlock(&tasklist_lock);

	/*
	 * Give "p" a good chance of killing itself before we
	 * retry to allocate memory unless "p" is current
	 */
	if (!test_thread_flag(TIF_MEMDIE))
		schedule_timeout_uninterruptible(1);
}