Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 596 insertions, 0 deletions

diff --git a/drivers/media/dvb-frontends/mt352.c b/drivers/media/dvb-frontends/mt352.c
new file mode 100644
index 000000000..7ae4d93f1
--- /dev/null
+++ b/drivers/media/dvb-frontends/mt352.c
@@ -0,0 +1,596 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  Driver for Zarlink DVB-T MT352 demodulator
+ *
+ *  Written by Holger Waechtler <holger@qanu.de>
+ *	 and Daniel Mack <daniel@qanu.de>
+ *
+ *  AVerMedia AVerTV DVB-T 771 support by
+ *       Wolfram Joost <dbox2@frokaschwei.de>
+ *
+ *  Support for Samsung TDTC9251DH01C(M) tuner
+ *  Copyright (C) 2004 Antonio Mancuso <antonio.mancuso@digitaltelevision.it>
+ *                     Amauri  Celani  <acelani@essegi.net>
+ *
+ *  DVICO FusionHDTV DVB-T1 and DVICO FusionHDTV DVB-T Lite support by
+ *       Christopher Pascoe <c.pascoe@itee.uq.edu.au>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+
+#include <media/dvb_frontend.h>
+#include "mt352_priv.h"
+#include "mt352.h"
+
+struct mt352_state {
+	struct i2c_adapter* i2c;
+	struct dvb_frontend frontend;
+
+	/* configuration settings */
+	struct mt352_config config;
+};
+
+static int debug;
+#define dprintk(args...) \
+	do { \
+		if (debug) printk(KERN_DEBUG "mt352: " args); \
+	} while (0)
+
+static int mt352_single_write(struct dvb_frontend *fe, u8 reg, u8 val)
+{
+	struct mt352_state* state = fe->demodulator_priv;
+	u8 buf[2] = { reg, val };
+	struct i2c_msg msg = { .addr = state->config.demod_address, .flags = 0,
+			       .buf = buf, .len = 2 };
+	int err = i2c_transfer(state->i2c, &msg, 1);
+	if (err != 1) {
+		printk("mt352_write() to reg %x failed (err = %d)!\n", reg, err);
+		return err;
+	}
+	return 0;
+}
+
+static int _mt352_write(struct dvb_frontend* fe, const u8 ibuf[], int ilen)
+{
+	int err,i;
+	for (i=0; i < ilen-1; i++)
+		if ((err = mt352_single_write(fe,ibuf[0]+i,ibuf[i+1])))
+			return err;
+
+	return 0;
+}
+
+static int mt352_read_register(struct mt352_state* state, u8 reg)
+{
+	int ret;
+	u8 b0 [] = { reg };
+	u8 b1 [] = { 0 };
+	struct i2c_msg msg [] = { { .addr = state->config.demod_address,
+				    .flags = 0,
+				    .buf = b0, .len = 1 },
+				  { .addr = state->config.demod_address,
+				    .flags = I2C_M_RD,
+				    .buf = b1, .len = 1 } };
+
+	ret = i2c_transfer(state->i2c, msg, 2);
+
+	if (ret != 2) {
+		printk("%s: readreg error (reg=%d, ret==%i)\n",
+		       __func__, reg, ret);
+		return ret;
+	}
+
+	return b1[0];
+}
+
+static int mt352_sleep(struct dvb_frontend* fe)
+{
+	static u8 mt352_softdown[] = { CLOCK_CTL, 0x20, 0x08 };
+
+	_mt352_write(fe, mt352_softdown, sizeof(mt352_softdown));
+	return 0;
+}
+
+static void mt352_calc_nominal_rate(struct mt352_state* state,
+				    u32 bandwidth,
+				    unsigned char *buf)
+{
+	u32 adc_clock = 20480; /* 20.340 MHz */
+	u32 bw,value;
+
+	switch (bandwidth) {
+	case 6000000:
+		bw = 6;
+		break;
+	case 7000000:
+		bw = 7;
+		break;
+	case 8000000:
+	default:
+		bw = 8;
+		break;
+	}
+	if (state->config.adc_clock)
+		adc_clock = state->config.adc_clock;
+
+	value = 64 * bw * (1<<16) / (7 * 8);
+	value = value * 1000 / adc_clock;
+	dprintk("%s: bw %d, adc_clock %d => 0x%x\n",
+		__func__, bw, adc_clock, value);
+	buf[0] = msb(value);
+	buf[1] = lsb(value);
+}
+
+static void mt352_calc_input_freq(struct mt352_state* state,
+				  unsigned char *buf)
+{
+	int adc_clock = 20480; /* 20.480000 MHz */
+	int if2       = 36167; /* 36.166667 MHz */
+	int ife,value;
+
+	if (state->config.adc_clock)
+		adc_clock = state->config.adc_clock;
+	if (state->config.if2)
+		if2 = state->config.if2;
+
+	if (adc_clock >= if2 * 2)
+		ife = if2;
+	else {
+		ife = adc_clock - (if2 % adc_clock);
+		if (ife > adc_clock / 2)
+			ife = adc_clock - ife;
+	}
+	value = -16374 * ife / adc_clock;
+	dprintk("%s: if2 %d, ife %d, adc_clock %d => %d / 0x%x\n",
+		__func__, if2, ife, adc_clock, value, value & 0x3fff);
+	buf[0] = msb(value);
+	buf[1] = lsb(value);
+}
+
+static int mt352_set_parameters(struct dvb_frontend *fe)
+{
+	struct dtv_frontend_properties *op = &fe->dtv_property_cache;
+	struct mt352_state* state = fe->demodulator_priv;
+	unsigned char buf[13];
+	static unsigned char tuner_go[] = { 0x5d, 0x01 };
+	static unsigned char fsm_go[]   = { 0x5e, 0x01 };
+	unsigned int tps = 0;
+
+	switch (op->code_rate_HP) {
+		case FEC_2_3:
+			tps |= (1 << 7);
+			break;
+		case FEC_3_4:
+			tps |= (2 << 7);
+			break;
+		case FEC_5_6:
+			tps |= (3 << 7);
+			break;
+		case FEC_7_8:
+			tps |= (4 << 7);
+			break;
+		case FEC_1_2:
+		case FEC_AUTO:
+			break;
+		default:
+			return -EINVAL;
+	}
+
+	switch (op->code_rate_LP) {
+		case FEC_2_3:
+			tps |= (1 << 4);
+			break;
+		case FEC_3_4:
+			tps |= (2 << 4);
+			break;
+		case FEC_5_6:
+			tps |= (3 << 4);
+			break;
+		case FEC_7_8:
+			tps |= (4 << 4);
+			break;
+		case FEC_1_2:
+		case FEC_AUTO:
+			break;
+		case FEC_NONE:
+			if (op->hierarchy == HIERARCHY_AUTO ||
+			    op->hierarchy == HIERARCHY_NONE)
+				break;
+			fallthrough;
+		default:
+			return -EINVAL;
+	}
+
+	switch (op->modulation) {
+		case QPSK:
+			break;
+		case QAM_AUTO:
+		case QAM_16:
+			tps |= (1 << 13);
+			break;
+		case QAM_64:
+			tps |= (2 << 13);
+			break;
+		default:
+			return -EINVAL;
+	}
+
+	switch (op->transmission_mode) {
+		case TRANSMISSION_MODE_2K:
+		case TRANSMISSION_MODE_AUTO:
+			break;
+		case TRANSMISSION_MODE_8K:
+			tps |= (1 << 0);
+			break;
+		default:
+			return -EINVAL;
+	}
+
+	switch (op->guard_interval) {
+		case GUARD_INTERVAL_1_32:
+		case GUARD_INTERVAL_AUTO:
+			break;
+		case GUARD_INTERVAL_1_16:
+			tps |= (1 << 2);
+			break;
+		case GUARD_INTERVAL_1_8:
+			tps |= (2 << 2);
+			break;
+		case GUARD_INTERVAL_1_4:
+			tps |= (3 << 2);
+			break;
+		default:
+			return -EINVAL;
+	}
+
+	switch (op->hierarchy) {
+		case HIERARCHY_AUTO:
+		case HIERARCHY_NONE:
+			break;
+		case HIERARCHY_1:
+			tps |= (1 << 10);
+			break;
+		case HIERARCHY_2:
+			tps |= (2 << 10);
+			break;
+		case HIERARCHY_4:
+			tps |= (3 << 10);
+			break;
+		default:
+			return -EINVAL;
+	}
+
+
+	buf[0] = TPS_GIVEN_1; /* TPS_GIVEN_1 and following registers */
+
+	buf[1] = msb(tps);      /* TPS_GIVEN_(1|0) */
+	buf[2] = lsb(tps);
+
+	buf[3] = 0x50;  // old
+//	buf[3] = 0xf4;  // pinnacle
+
+	mt352_calc_nominal_rate(state, op->bandwidth_hz, buf+4);
+	mt352_calc_input_freq(state, buf+6);
+
+	if (state->config.no_tuner) {
+		if (fe->ops.tuner_ops.set_params) {
+			fe->ops.tuner_ops.set_params(fe);
+			if (fe->ops.i2c_gate_ctrl)
+				fe->ops.i2c_gate_ctrl(fe, 0);
+		}
+
+		_mt352_write(fe, buf, 8);
+		_mt352_write(fe, fsm_go, 2);
+	} else {
+		if (fe->ops.tuner_ops.calc_regs) {
+			fe->ops.tuner_ops.calc_regs(fe, buf+8, 5);
+			buf[8] <<= 1;
+			_mt352_write(fe, buf, sizeof(buf));
+			_mt352_write(fe, tuner_go, 2);
+		}
+	}
+
+	return 0;
+}
+
+static int mt352_get_parameters(struct dvb_frontend* fe,
+				struct dtv_frontend_properties *op)
+{
+	struct mt352_state* state = fe->demodulator_priv;
+	u16 tps;
+	u16 div;
+	u8 trl;
+	static const u8 tps_fec_to_api[8] =
+	{
+		FEC_1_2,
+		FEC_2_3,
+		FEC_3_4,
+		FEC_5_6,
+		FEC_7_8,
+		FEC_AUTO,
+		FEC_AUTO,
+		FEC_AUTO
+	};
+
+	if ( (mt352_read_register(state,0x00) & 0xC0) != 0xC0 )
+		return -EINVAL;
+
+	/* Use TPS_RECEIVED-registers, not the TPS_CURRENT-registers because
+	 * the mt352 sometimes works with the wrong parameters
+	 */
+	tps = (mt352_read_register(state, TPS_RECEIVED_1) << 8) | mt352_read_register(state, TPS_RECEIVED_0);
+	div = (mt352_read_register(state, CHAN_START_1) << 8) | mt352_read_register(state, CHAN_START_0);
+	trl = mt352_read_register(state, TRL_NOMINAL_RATE_1);
+
+	op->code_rate_HP = tps_fec_to_api[(tps >> 7) & 7];
+	op->code_rate_LP = tps_fec_to_api[(tps >> 4) & 7];
+
+	switch ( (tps >> 13) & 3)
+	{
+		case 0:
+			op->modulation = QPSK;
+			break;
+		case 1:
+			op->modulation = QAM_16;
+			break;
+		case 2:
+			op->modulation = QAM_64;
+			break;
+		default:
+			op->modulation = QAM_AUTO;
+			break;
+	}
+
+	op->transmission_mode = (tps & 0x01) ? TRANSMISSION_MODE_8K : TRANSMISSION_MODE_2K;
+
+	switch ( (tps >> 2) & 3)
+	{
+		case 0:
+			op->guard_interval = GUARD_INTERVAL_1_32;
+			break;
+		case 1:
+			op->guard_interval = GUARD_INTERVAL_1_16;
+			break;
+		case 2:
+			op->guard_interval = GUARD_INTERVAL_1_8;
+			break;
+		case 3:
+			op->guard_interval = GUARD_INTERVAL_1_4;
+			break;
+		default:
+			op->guard_interval = GUARD_INTERVAL_AUTO;
+			break;
+	}
+
+	switch ( (tps >> 10) & 7)
+	{
+		case 0:
+			op->hierarchy = HIERARCHY_NONE;
+			break;
+		case 1:
+			op->hierarchy = HIERARCHY_1;
+			break;
+		case 2:
+			op->hierarchy = HIERARCHY_2;
+			break;
+		case 3:
+			op->hierarchy = HIERARCHY_4;
+			break;
+		default:
+			op->hierarchy = HIERARCHY_AUTO;
+			break;
+	}
+
+	op->frequency = (500 * (div - IF_FREQUENCYx6)) / 3 * 1000;
+
+	if (trl == 0x72)
+		op->bandwidth_hz = 8000000;
+	else if (trl == 0x64)
+		op->bandwidth_hz = 7000000;
+	else
+		op->bandwidth_hz = 6000000;
+
+
+	if (mt352_read_register(state, STATUS_2) & 0x02)
+		op->inversion = INVERSION_OFF;
+	else
+		op->inversion = INVERSION_ON;
+
+	return 0;
+}
+
+static int mt352_read_status(struct dvb_frontend *fe, enum fe_status *status)
+{
+	struct mt352_state* state = fe->demodulator_priv;
+	int s0, s1, s3;
+
+	/* FIXME:
+	 *
+	 * The MT352 design manual from Zarlink states (page 46-47):
+	 *
+	 * Notes about the TUNER_GO register:
+	 *
+	 * If the Read_Tuner_Byte (bit-1) is activated, then the tuner status
+	 * byte is copied from the tuner to the STATUS_3 register and
+	 * completion of the read operation is indicated by bit-5 of the
+	 * INTERRUPT_3 register.
+	 */
+
+	if ((s0 = mt352_read_register(state, STATUS_0)) < 0)
+		return -EREMOTEIO;
+	if ((s1 = mt352_read_register(state, STATUS_1)) < 0)
+		return -EREMOTEIO;
+	if ((s3 = mt352_read_register(state, STATUS_3)) < 0)
+		return -EREMOTEIO;
+
+	*status = 0;
+	if (s0 & (1 << 4))
+		*status |= FE_HAS_CARRIER;
+	if (s0 & (1 << 1))
+		*status |= FE_HAS_VITERBI;
+	if (s0 & (1 << 5))
+		*status |= FE_HAS_LOCK;
+	if (s1 & (1 << 1))
+		*status |= FE_HAS_SYNC;
+	if (s3 & (1 << 6))
+		*status |= FE_HAS_SIGNAL;
+
+	if ((*status & (FE_HAS_CARRIER | FE_HAS_VITERBI | FE_HAS_SYNC)) !=
+		      (FE_HAS_CARRIER | FE_HAS_VITERBI | FE_HAS_SYNC))
+		*status &= ~FE_HAS_LOCK;
+
+	return 0;
+}
+
+static int mt352_read_ber(struct dvb_frontend* fe, u32* ber)
+{
+	struct mt352_state* state = fe->demodulator_priv;
+
+	*ber = (mt352_read_register (state, RS_ERR_CNT_2) << 16) |
+	       (mt352_read_register (state, RS_ERR_CNT_1) << 8) |
+	       (mt352_read_register (state, RS_ERR_CNT_0));
+
+	return 0;
+}
+
+static int mt352_read_signal_strength(struct dvb_frontend* fe, u16* strength)
+{
+	struct mt352_state* state = fe->demodulator_priv;
+
+	/* align the 12 bit AGC gain with the most significant bits */
+	u16 signal = ((mt352_read_register(state, AGC_GAIN_1) & 0x0f) << 12) |
+		(mt352_read_register(state, AGC_GAIN_0) << 4);
+
+	/* inverse of gain is signal strength */
+	*strength = ~signal;
+	return 0;
+}
+
+static int mt352_read_snr(struct dvb_frontend* fe, u16* snr)
+{
+	struct mt352_state* state = fe->demodulator_priv;
+
+	u8 _snr = mt352_read_register (state, SNR);
+	*snr = (_snr << 8) | _snr;
+
+	return 0;
+}
+
+static int mt352_read_ucblocks(struct dvb_frontend* fe, u32* ucblocks)
+{
+	struct mt352_state* state = fe->demodulator_priv;
+
+	*ucblocks = (mt352_read_register (state,  RS_UBC_1) << 8) |
+		    (mt352_read_register (state,  RS_UBC_0));
+
+	return 0;
+}
+
+static int mt352_get_tune_settings(struct dvb_frontend* fe, struct dvb_frontend_tune_settings* fe_tune_settings)
+{
+	fe_tune_settings->min_delay_ms = 800;
+	fe_tune_settings->step_size = 0;
+	fe_tune_settings->max_drift = 0;
+
+	return 0;
+}
+
+static int mt352_init(struct dvb_frontend* fe)
+{
+	struct mt352_state* state = fe->demodulator_priv;
+
+	static u8 mt352_reset_attach [] = { RESET, 0xC0 };
+
+	dprintk("%s: hello\n",__func__);
+
+	if ((mt352_read_register(state, CLOCK_CTL) & 0x10) == 0 ||
+	    (mt352_read_register(state, CONFIG) & 0x20) == 0) {
+
+		/* Do a "hard" reset */
+		_mt352_write(fe, mt352_reset_attach, sizeof(mt352_reset_attach));
+		return state->config.demod_init(fe);
+	}
+
+	return 0;
+}
+
+static void mt352_release(struct dvb_frontend* fe)
+{
+	struct mt352_state* state = fe->demodulator_priv;
+	kfree(state);
+}
+
+static const struct dvb_frontend_ops mt352_ops;
+
+struct dvb_frontend* mt352_attach(const struct mt352_config* config,
+				  struct i2c_adapter* i2c)
+{
+	struct mt352_state* state = NULL;
+
+	/* allocate memory for the internal state */
+	state = kzalloc_obj(struct mt352_state);
+	if (state == NULL) goto error;
+
+	/* setup the state */
+	state->i2c = i2c;
+	memcpy(&state->config,config,sizeof(struct mt352_config));
+
+	/* check if the demod is there */
+	if (mt352_read_register(state, CHIP_ID) != ID_MT352) goto error;
+
+	/* create dvb_frontend */
+	memcpy(&state->frontend.ops, &mt352_ops, sizeof(struct dvb_frontend_ops));
+	state->frontend.demodulator_priv = state;
+	return &state->frontend;
+
+error:
+	kfree(state);
+	return NULL;
+}
+
+static const struct dvb_frontend_ops mt352_ops = {
+	.delsys = { SYS_DVBT },
+	.info = {
+		.name			= "Zarlink MT352 DVB-T",
+		.frequency_min_hz	= 174 * MHz,
+		.frequency_max_hz	= 862 * MHz,
+		.frequency_stepsize_hz	= 166667,
+		.caps = FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 |
+			FE_CAN_FEC_3_4 | FE_CAN_FEC_5_6 | FE_CAN_FEC_7_8 |
+			FE_CAN_FEC_AUTO |
+			FE_CAN_QPSK | FE_CAN_QAM_16 | FE_CAN_QAM_64 | FE_CAN_QAM_AUTO |
+			FE_CAN_TRANSMISSION_MODE_AUTO | FE_CAN_GUARD_INTERVAL_AUTO |
+			FE_CAN_HIERARCHY_AUTO | FE_CAN_RECOVER |
+			FE_CAN_MUTE_TS
+	},
+
+	.release = mt352_release,
+
+	.init = mt352_init,
+	.sleep = mt352_sleep,
+	.write = _mt352_write,
+
+	.set_frontend = mt352_set_parameters,
+	.get_frontend = mt352_get_parameters,
+	.get_tune_settings = mt352_get_tune_settings,
+
+	.read_status = mt352_read_status,
+	.read_ber = mt352_read_ber,
+	.read_signal_strength = mt352_read_signal_strength,
+	.read_snr = mt352_read_snr,
+	.read_ucblocks = mt352_read_ucblocks,
+};
+
+module_param(debug, int, 0644);
+MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
+
+MODULE_DESCRIPTION("Zarlink MT352 DVB-T Demodulator driver");
+MODULE_AUTHOR("Holger Waechtler, Daniel Mack, Antonio Mancuso");
+MODULE_LICENSE("GPL");
+
+EXPORT_SYMBOL_GPL(mt352_attach);