On Tue, Apr 2, 2019 at 12:48 PM Sasha Levin <sashal(a)kernel.org> wrote:
>
> Hi,
>
> [This is an automated email]
>
> This commit has been processed because it contains a -stable tag.
> The stable tag indicates that it's relevant for the following trees: 4.9+
>
> The bot has tested the following trees: v5.0.5, v4.19.32, v4.14.109, v4.9.166.
> How should we proceed with this patch?
I can manually generate versions for 4.9, 4.14 and 4.19 stable trees
when this one hit mainline.
From: Eric Biggers <ebiggers(a)google.com>
[This is essentially the same as the corresponding patch to GCM.]
CCM instances can be created by either the "ccm" template, which only
allows choosing the block cipher, e.g. "ccm(aes)"; or by "ccm_base",
which allows choosing the ctr and cbcmac implementations, e.g.
"ccm_base(ctr(aes-generic),cbcmac(aes-generic))".
However, a "ccm_base" instance prevents a "ccm" instance from being
registered using the same implementations. Nor will the instance be
found by lookups of "ccm". This can be used as a denial of service.
Moreover, "ccm_base" instances are never tested by the crypto
self-tests, even if there are compatible "ccm" tests.
The root cause of these problems is that instances of the two templates
use different cra_names. Therefore, fix these problems by making
"ccm_base" instances set the same cra_name as "ccm" instances, e.g.
"ccm(aes)" instead of "ccm_base(ctr(aes-generic),cbcmac(aes-generic))".
This requires extracting the block cipher name from the name of the ctr
algorithm, which means starting to require that the stream cipher really
be ctr and not something else. But it would be pretty bizarre if anyone
was actually relying on being able to use a non-ctr stream cipher here.
Fixes: 4a49b499dfa0 ("[CRYPTO] ccm: Added CCM mode")
Cc: stable(a)vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers(a)google.com>
---
crypto/ccm.c | 38 ++++++++++++--------------------------
1 file changed, 12 insertions(+), 26 deletions(-)
diff --git a/crypto/ccm.c b/crypto/ccm.c
index 50df8f001c1c9..3bb49776450b7 100644
--- a/crypto/ccm.c
+++ b/crypto/ccm.c
@@ -458,7 +458,6 @@ static void crypto_ccm_free(struct aead_instance *inst)
static int crypto_ccm_create_common(struct crypto_template *tmpl,
struct rtattr **tb,
- const char *full_name,
const char *ctr_name,
const char *mac_name)
{
@@ -509,23 +508,22 @@ static int crypto_ccm_create_common(struct crypto_template *tmpl,
ctr = crypto_spawn_skcipher_alg(&ictx->ctr);
- /* Not a stream cipher? */
+ /* Must be CTR mode with 16-byte blocks. */
err = -EINVAL;
- if (ctr->base.cra_blocksize != 1)
+ if (strncmp(ctr->base.cra_name, "ctr(", 4) != 0 ||
+ crypto_skcipher_alg_ivsize(ctr) != 16)
goto err_drop_ctr;
- /* We want the real thing! */
- if (crypto_skcipher_alg_ivsize(ctr) != 16)
+ err = -ENAMETOOLONG;
+ if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
+ "ccm(%s", ctr->base.cra_name + 4) >= CRYPTO_MAX_ALG_NAME)
goto err_drop_ctr;
- err = -ENAMETOOLONG;
if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
"ccm_base(%s,%s)", ctr->base.cra_driver_name,
mac->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
goto err_drop_ctr;
- memcpy(inst->alg.base.cra_name, full_name, CRYPTO_MAX_ALG_NAME);
-
inst->alg.base.cra_flags = ctr->base.cra_flags & CRYPTO_ALG_ASYNC;
inst->alg.base.cra_priority = (mac->base.cra_priority +
ctr->base.cra_priority) / 2;
@@ -567,7 +565,6 @@ static int crypto_ccm_create(struct crypto_template *tmpl, struct rtattr **tb)
const char *cipher_name;
char ctr_name[CRYPTO_MAX_ALG_NAME];
char mac_name[CRYPTO_MAX_ALG_NAME];
- char full_name[CRYPTO_MAX_ALG_NAME];
cipher_name = crypto_attr_alg_name(tb[1]);
if (IS_ERR(cipher_name))
@@ -581,35 +578,24 @@ static int crypto_ccm_create(struct crypto_template *tmpl, struct rtattr **tb)
cipher_name) >= CRYPTO_MAX_ALG_NAME)
return -ENAMETOOLONG;
- if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "ccm(%s)", cipher_name) >=
- CRYPTO_MAX_ALG_NAME)
- return -ENAMETOOLONG;
-
- return crypto_ccm_create_common(tmpl, tb, full_name, ctr_name,
- mac_name);
+ return crypto_ccm_create_common(tmpl, tb, ctr_name, mac_name);
}
static int crypto_ccm_base_create(struct crypto_template *tmpl,
struct rtattr **tb)
{
const char *ctr_name;
- const char *cipher_name;
- char full_name[CRYPTO_MAX_ALG_NAME];
+ const char *mac_name;
ctr_name = crypto_attr_alg_name(tb[1]);
if (IS_ERR(ctr_name))
return PTR_ERR(ctr_name);
- cipher_name = crypto_attr_alg_name(tb[2]);
- if (IS_ERR(cipher_name))
- return PTR_ERR(cipher_name);
-
- if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "ccm_base(%s,%s)",
- ctr_name, cipher_name) >= CRYPTO_MAX_ALG_NAME)
- return -ENAMETOOLONG;
+ mac_name = crypto_attr_alg_name(tb[2]);
+ if (IS_ERR(mac_name))
+ return PTR_ERR(mac_name);
- return crypto_ccm_create_common(tmpl, tb, full_name, ctr_name,
- cipher_name);
+ return crypto_ccm_create_common(tmpl, tb, ctr_name, mac_name);
}
static int crypto_rfc4309_setkey(struct crypto_aead *parent, const u8 *key,
--
2.21.0
Currently, compat tasks running on arm64 can allocate memory up to
TASK_SIZE_32 (UL(0x100000000)).
This means that mmap() allocations, if we treat them as returning an
array, are not compliant with the sections 6.5.8 of the C standard
(C99) which states that: "If the expression P points to an element of
an array object and the expression Q points to the last element of the
same array object, the pointer expression Q+1 compares greater than P".
Redefine TASK_SIZE_32 to address the issue.
Cc: Catalin Marinas <catalin.marinas(a)arm.com>
Cc: Will Deacon <will.deacon(a)arm.com>
Cc: Jann Horn <jannh(a)google.com>
Cc: <stable(a)vger.kernel.org>
Reported-by: Jann Horn <jannh(a)google.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino(a)arm.com>
---
arch/arm64/include/asm/processor.h | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h
index 5d9ce62bdebd..9c831d9d3cd2 100644
--- a/arch/arm64/include/asm/processor.h
+++ b/arch/arm64/include/asm/processor.h
@@ -57,7 +57,15 @@
#define TASK_SIZE_64 (UL(1) << vabits_user)
#ifdef CONFIG_COMPAT
+#ifdef CONFIG_ARM64_64K_PAGES
+/*
+ * With CONFIG_ARM64_64K_PAGES enabled, the last page is occupied
+ * by the compact vectors page.
+ */
#define TASK_SIZE_32 UL(0x100000000)
+#else
+#define TASK_SIZE_32 (UL(0x100000000) - PAGE_SIZE)
+#endif /* CONFIG_ARM64_64K_PAGES */
#define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \
TASK_SIZE_32 : TASK_SIZE_64)
#define TASK_SIZE_OF(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT) ? \
--
2.21.0
Spurious interrupt support was adding to perf in:
commit 63e6be6d98e1 ("perf, x86: Catch spurious interrupts after disabling counters")
The two previous patches (resolving the race condition when disabling a
PMC and NMI latency mitigation) allow for the removal of this older
spurious interrupt support.
Currently in x86_pmu_stop(), the bit for the PMC in the active_mask bitmap
is cleared before disabling the PMC, which sets up a race condition. This
race condition was mitigated by introducing the running bitmap. That race
condition can be eliminated by first disabling the PMC, waiting for PMC
reset on overflow and then clearing the bit for the PMC in the active_mask
bitmap. The NMI handler will not re-enable a disabled counter.
If x86_pmu_stop() is called from the perf NMI handler, the NMI latency
mitigation support will guard against any unhandled NMI messages.
Cc: <stable(a)vger.kernel.org> # 4.14.x-
Signed-off-by: Tom Lendacky <thomas.lendacky(a)amd.com>
---
arch/x86/events/amd/core.c | 19 ++++++++++++++++++-
arch/x86/events/core.c | 13 +++----------
2 files changed, 21 insertions(+), 11 deletions(-)
diff --git a/arch/x86/events/amd/core.c b/arch/x86/events/amd/core.c
index 8f06ec0e673b..22d6667c7063 100644
--- a/arch/x86/events/amd/core.c
+++ b/arch/x86/events/amd/core.c
@@ -490,6 +490,23 @@ static void amd_pmu_disable_all(void)
}
}
+static void amd_pmu_disable_event(struct perf_event *event)
+{
+ x86_pmu_disable_event(event);
+
+ /*
+ * This can be called from NMI context (via x86_pmu_stop). The counter
+ * may have overflowed, but either way, we'll never see it get reset
+ * by the NMI if we're already in the NMI. And the NMI latency support
+ * below will take care of any pending NMI that might have been
+ * generated by the overflow.
+ */
+ if (in_nmi())
+ return;
+
+ amd_pmu_wait_on_overflow(event->hw.idx);
+}
+
/*
* Because of NMI latency, if multiple PMC counters are active or other sources
* of NMIs are received, the perf NMI handler can handle one or more overflowed
@@ -737,7 +754,7 @@ static __initconst const struct x86_pmu amd_pmu = {
.disable_all = amd_pmu_disable_all,
.enable_all = x86_pmu_enable_all,
.enable = x86_pmu_enable_event,
- .disable = x86_pmu_disable_event,
+ .disable = amd_pmu_disable_event,
.hw_config = amd_pmu_hw_config,
.schedule_events = x86_schedule_events,
.eventsel = MSR_K7_EVNTSEL0,
diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index e2b1447192a8..81911e11a15d 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -1349,8 +1349,9 @@ void x86_pmu_stop(struct perf_event *event, int flags)
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
struct hw_perf_event *hwc = &event->hw;
- if (__test_and_clear_bit(hwc->idx, cpuc->active_mask)) {
+ if (test_bit(hwc->idx, cpuc->active_mask)) {
x86_pmu.disable(event);
+ __clear_bit(hwc->idx, cpuc->active_mask);
cpuc->events[hwc->idx] = NULL;
WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
hwc->state |= PERF_HES_STOPPED;
@@ -1447,16 +1448,8 @@ int x86_pmu_handle_irq(struct pt_regs *regs)
apic_write(APIC_LVTPC, APIC_DM_NMI);
for (idx = 0; idx < x86_pmu.num_counters; idx++) {
- if (!test_bit(idx, cpuc->active_mask)) {
- /*
- * Though we deactivated the counter some cpus
- * might still deliver spurious interrupts still
- * in flight. Catch them:
- */
- if (__test_and_clear_bit(idx, cpuc->running))
- handled++;
+ if (!test_bit(idx, cpuc->active_mask))
continue;
- }
event = cpuc->events[idx];
--
2.17.1
On AMD processors, the detection of an overflowed PMC counter in the NMI
handler relies on the current value of the PMC. So, for example, to check
for overflow on a 48-bit counter, bit 47 is checked to see if it is 1 (not
overflowed) or 0 (overflowed).
When the perf NMI handler executes it does not know in advance which PMC
counters have overflowed. As such, the NMI handler will process all active
PMC counters that have overflowed. NMI latency in newer AMD processors can
result in multiple overflowed PMC counters being processed in one NMI and
then a subsequent NMI, that does not appear to be a back-to-back NMI, not
finding any PMC counters that have overflowed. This may appear to be an
unhandled NMI resulting in either a panic or a series of messages,
depending on how the kernel was configured.
To mitigate this issue, add an AMD handle_irq callback function,
amd_pmu_handle_irq(), that will invoke the common x86_pmu_handle_irq()
function and upon return perform some additional processing that will
indicate if the NMI has been handled or would have been handled had an
earlier NMI not handled the overflowed PMC. Using a per-CPU variable, a
minimum value of the number of active PMCs or 2 will be set whenever a
PMC is active. This is used to indicate the possible number of NMIs that
can still occur. The value of 2 is used for when an NMI does not arrive
at the LAPIC in time to be collapsed into an already pending NMI. Each
time the function is called without having handled an overflowed counter,
the per-CPU value is checked. If the value is non-zero, it is decremented
and the NMI indicates that it handled the NMI. If the value is zero, then
the NMI indicates that it did not handle the NMI.
Cc: <stable(a)vger.kernel.org> # 4.14.x-
Signed-off-by: Tom Lendacky <thomas.lendacky(a)amd.com>
---
arch/x86/events/amd/core.c | 56 +++++++++++++++++++++++++++++++++++++-
1 file changed, 55 insertions(+), 1 deletion(-)
diff --git a/arch/x86/events/amd/core.c b/arch/x86/events/amd/core.c
index beb132593622..8f06ec0e673b 100644
--- a/arch/x86/events/amd/core.c
+++ b/arch/x86/events/amd/core.c
@@ -4,10 +4,13 @@
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/delay.h>
+#include <linux/nmi.h>
#include <asm/apicdef.h>
#include "../perf_event.h"
+static DEFINE_PER_CPU(unsigned int, perf_nmi_counter);
+
static __initconst const u64 amd_hw_cache_event_ids
[PERF_COUNT_HW_CACHE_MAX]
[PERF_COUNT_HW_CACHE_OP_MAX]
@@ -487,6 +490,57 @@ static void amd_pmu_disable_all(void)
}
}
+/*
+ * Because of NMI latency, if multiple PMC counters are active or other sources
+ * of NMIs are received, the perf NMI handler can handle one or more overflowed
+ * PMC counters outside of the NMI associated with the PMC overflow. If the NMI
+ * doesn't arrive at the LAPIC in time to become a pending NMI, then the kernel
+ * back-to-back NMI support won't be active. This PMC handler needs to take into
+ * account that this can occur, otherwise this could result in unknown NMI
+ * messages being issued. Examples of this is PMC overflow while in the NMI
+ * handler when multiple PMCs are active or PMC overflow while handling some
+ * other source of an NMI.
+ *
+ * Attempt to mitigate this by using the number of active PMCs to determine
+ * whether to return NMI_HANDLED if the perf NMI handler did not handle/reset
+ * any PMCs. The per-CPU perf_nmi_counter variable is set to a minimum of the
+ * number of active PMCs or 2. The value of 2 is used in case an NMI does not
+ * arrive at the LAPIC in time to be collapsed into an already pending NMI.
+ */
+static int amd_pmu_handle_irq(struct pt_regs *regs)
+{
+ struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+ int active, handled;
+
+ /*
+ * Obtain the active count before calling x86_pmu_handle_irq() since
+ * it is possible that x86_pmu_handle_irq() may make a counter
+ * inactive (through x86_pmu_stop).
+ */
+ active = __bitmap_weight(cpuc->active_mask, X86_PMC_IDX_MAX);
+
+ /* Process any counter overflows */
+ handled = x86_pmu_handle_irq(regs);
+
+ /*
+ * If a counter was handled, record the number of possible remaining
+ * NMIs that can occur.
+ */
+ if (handled) {
+ this_cpu_write(perf_nmi_counter,
+ min_t(unsigned int, 2, active));
+
+ return handled;
+ }
+
+ if (!this_cpu_read(perf_nmi_counter))
+ return NMI_DONE;
+
+ this_cpu_dec(perf_nmi_counter);
+
+ return NMI_HANDLED;
+}
+
static struct event_constraint *
amd_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
struct perf_event *event)
@@ -679,7 +733,7 @@ static ssize_t amd_event_sysfs_show(char *page, u64 config)
static __initconst const struct x86_pmu amd_pmu = {
.name = "AMD",
- .handle_irq = x86_pmu_handle_irq,
+ .handle_irq = amd_pmu_handle_irq,
.disable_all = amd_pmu_disable_all,
.enable_all = x86_pmu_enable_all,
.enable = x86_pmu_enable_event,
--
2.17.1
On AMD processors, the detection of an overflowed counter in the NMI
handler relies on the current value of the counter. So, for example, to
check for overflow on a 48 bit counter, bit 47 is checked to see if it
is 1 (not overflowed) or 0 (overflowed).
There is currently a race condition present when disabling and then
updating the PMC. Increased NMI latency in newer AMD processors makes this
race condition more pronounced. If the counter value has overflowed, it is
possible to update the PMC value before the NMI handler can run. The
updated PMC value is not an overflowed value, so when the perf NMI handler
does run, it will not find an overflowed counter. This may appear as an
unknown NMI resulting in either a panic or a series of messages, depending
on how the kernel is configured.
To eliminate this race condition, the PMC value must be checked after
disabling the counter. Add an AMD function, amd_pmu_disable_all(), that
will wait for the NMI handler to reset any active and overflowed counter
after calling x86_pmu_disable_all().
Cc: <stable(a)vger.kernel.org> # 4.14.x-
Signed-off-by: Tom Lendacky <thomas.lendacky(a)amd.com>
---
arch/x86/events/amd/core.c | 64 ++++++++++++++++++++++++++++++++++++--
1 file changed, 61 insertions(+), 3 deletions(-)
diff --git a/arch/x86/events/amd/core.c b/arch/x86/events/amd/core.c
index 7d2d7c801dba..beb132593622 100644
--- a/arch/x86/events/amd/core.c
+++ b/arch/x86/events/amd/core.c
@@ -3,6 +3,7 @@
#include <linux/types.h>
#include <linux/init.h>
#include <linux/slab.h>
+#include <linux/delay.h>
#include <asm/apicdef.h>
#include "../perf_event.h"
@@ -429,6 +430,63 @@ static void amd_pmu_cpu_dead(int cpu)
}
}
+/*
+ * When a PMC counter overflows, an NMI is used to process the event and
+ * reset the counter. NMI latency can result in the counter being updated
+ * before the NMI can run, which can result in what appear to be spurious
+ * NMIs. This function is intended to wait for the NMI to run and reset
+ * the counter to avoid possible unhandled NMI messages.
+ */
+#define OVERFLOW_WAIT_COUNT 50
+static void amd_pmu_wait_on_overflow(int idx)
+{
+ unsigned int i;
+ u64 counter;
+
+ /*
+ * Wait for the counter to be reset if it has overflowed. This loop
+ * should exit very, very quickly, but just in case, don't wait
+ * forever...
+ */
+ for (i = 0; i < OVERFLOW_WAIT_COUNT; i++) {
+ rdmsrl(x86_pmu_event_addr(idx), counter);
+ if (counter & (1ULL << (x86_pmu.cntval_bits - 1)))
+ break;
+
+ /* Might be in IRQ context, so can't sleep */
+ udelay(1);
+ }
+}
+
+static void amd_pmu_disable_all(void)
+{
+ struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+ int idx;
+
+ x86_pmu_disable_all();
+
+ /*
+ * This shouldn't be called from NMI context, but add a safeguard here
+ * to return, since if we're in NMI context we can't wait for an NMI
+ * to reset an overflowed counter value.
+ */
+ if (in_nmi())
+ return;
+
+ /*
+ * Check each counter for overflow and wait for it to be reset by the
+ * NMI if it has overflowed. This relies on the fact that all active
+ * counters are always enabled when this function is caled and
+ * ARCH_PERFMON_EVENTSEL_INT is always set.
+ */
+ for (idx = 0; idx < x86_pmu.num_counters; idx++) {
+ if (!test_bit(idx, cpuc->active_mask))
+ continue;
+
+ amd_pmu_wait_on_overflow(idx);
+ }
+}
+
static struct event_constraint *
amd_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
struct perf_event *event)
@@ -622,7 +680,7 @@ static ssize_t amd_event_sysfs_show(char *page, u64 config)
static __initconst const struct x86_pmu amd_pmu = {
.name = "AMD",
.handle_irq = x86_pmu_handle_irq,
- .disable_all = x86_pmu_disable_all,
+ .disable_all = amd_pmu_disable_all,
.enable_all = x86_pmu_enable_all,
.enable = x86_pmu_enable_event,
.disable = x86_pmu_disable_event,
@@ -732,7 +790,7 @@ void amd_pmu_enable_virt(void)
cpuc->perf_ctr_virt_mask = 0;
/* Reload all events */
- x86_pmu_disable_all();
+ amd_pmu_disable_all();
x86_pmu_enable_all(0);
}
EXPORT_SYMBOL_GPL(amd_pmu_enable_virt);
@@ -750,7 +808,7 @@ void amd_pmu_disable_virt(void)
cpuc->perf_ctr_virt_mask = AMD64_EVENTSEL_HOSTONLY;
/* Reload all events */
- x86_pmu_disable_all();
+ amd_pmu_disable_all();
x86_pmu_enable_all(0);
}
EXPORT_SYMBOL_GPL(amd_pmu_disable_virt);
--
2.17.1
This patch uses the device description to clearly identity a device
attached to the bus. It is needed as the currently useed mdevX
notation is not sufficiant in case more than one network
interface controller is being used at the same time.
Cc: stable(a)vger.kernel.org
Signed-off-by: Christian Gromm <christian.gromm(a)microchip.com>
---
drivers/staging/most/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/staging/most/core.c b/drivers/staging/most/core.c
index a5df53e..e0a6806 100644
--- a/drivers/staging/most/core.c
+++ b/drivers/staging/most/core.c
@@ -1467,7 +1467,7 @@ int most_register_interface(struct most_interface *iface)
INIT_LIST_HEAD(&iface->p->channel_list);
iface->p->dev_id = id;
- snprintf(iface->p->name, STRING_SIZE, "mdev%d", id);
+ strcpy(iface->p->name, iface->description);
iface->dev.init_name = iface->p->name;
iface->dev.bus = &mc.bus;
iface->dev.parent = &mc.dev;
--
2.7.4
This is a note to let you know that I've just added the patch titled
iio: ad_sigma_delta: select channel when reading register
to my staging git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git
in the staging-linus branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.
If you have any questions about this process, please let me know.
>From fccfb9ce70ed4ea7a145f77b86de62e38178517f Mon Sep 17 00:00:00 2001
From: Dragos Bogdan <dragos.bogdan(a)analog.com>
Date: Tue, 19 Mar 2019 12:47:00 +0200
Subject: iio: ad_sigma_delta: select channel when reading register
The desired channel has to be selected in order to correctly fill the
buffer with the corresponding data.
The `ad_sd_write_reg()` already does this, but for the
`ad_sd_read_reg_raw()` this was omitted.
Fixes: af3008485ea03 ("iio:adc: Add common code for ADI Sigma Delta devices")
Signed-off-by: Dragos Bogdan <dragos.bogdan(a)analog.com>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean(a)analog.com>
Cc: <Stable(a)vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron(a)huawei.com>
---
drivers/iio/adc/ad_sigma_delta.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/iio/adc/ad_sigma_delta.c b/drivers/iio/adc/ad_sigma_delta.c
index ff5f2da2e1b1..54d9978b2740 100644
--- a/drivers/iio/adc/ad_sigma_delta.c
+++ b/drivers/iio/adc/ad_sigma_delta.c
@@ -121,6 +121,7 @@ static int ad_sd_read_reg_raw(struct ad_sigma_delta *sigma_delta,
if (sigma_delta->info->has_registers) {
data[0] = reg << sigma_delta->info->addr_shift;
data[0] |= sigma_delta->info->read_mask;
+ data[0] |= sigma_delta->comm;
spi_message_add_tail(&t[0], &m);
}
spi_message_add_tail(&t[1], &m);
--
2.21.0
This is a note to let you know that I've just added the patch titled
iio: cros_ec: Fix the maths for gyro scale calculation
to my staging git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git
in the staging-linus branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.
If you have any questions about this process, please let me know.
>From 3d02d7082e5823598090530c3988a35f69689943 Mon Sep 17 00:00:00 2001
From: Gwendal Grignou <gwendal(a)chromium.org>
Date: Wed, 13 Mar 2019 12:40:02 +0100
Subject: iio: cros_ec: Fix the maths for gyro scale calculation
Calculation did not use IIO_DEGREE_TO_RAD and implemented a variant to
avoid precision loss as we aim a nano value. The offset added to avoid
rounding error, though, doesn't give us a close result to the expected
value. E.g.
For 1000dps, the result should be:
(1000 * pi ) / 180 >> 15 ~= 0.000532632218
But with current calculation we get
$ cat scale
0.000547890
Fix the calculation by just doing the maths involved for a nano value
val * pi * 10e12 / (180 * 2^15)
so we get a closer result.
$ cat scale
0.000532632
Fixes: c14dca07a31d ("iio: cros_ec_sensors: add ChromeOS EC Contiguous Sensors driver")
Signed-off-by: Gwendal Grignou <gwendal(a)chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo(a)collabora.com>
Cc: <Stable(a)vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron(a)huawei.com>
---
drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
index 89cb0066a6e0..8d76afb87d87 100644
--- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
+++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
@@ -103,9 +103,10 @@ static int cros_ec_sensors_read(struct iio_dev *indio_dev,
* Do not use IIO_DEGREE_TO_RAD to avoid precision
* loss. Round to the nearest integer.
*/
- *val = div_s64(val64 * 314159 + 9000000ULL, 1000);
- *val2 = 18000 << (CROS_EC_SENSOR_BITS - 1);
- ret = IIO_VAL_FRACTIONAL;
+ *val = 0;
+ *val2 = div_s64(val64 * 3141592653ULL,
+ 180 << (CROS_EC_SENSOR_BITS - 1));
+ ret = IIO_VAL_INT_PLUS_NANO;
break;
case MOTIONSENSE_TYPE_MAG:
/*
--
2.21.0
This is a note to let you know that I've just added the patch titled
iio: dac: mcp4725: add missing powerdown bits in store eeprom
to my staging git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git
in the staging-linus branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.
If you have any questions about this process, please let me know.
>From 06003531502d06bc89d32528f6ec96bf978790f9 Mon Sep 17 00:00:00 2001
From: Jean-Francois Dagenais <jeff.dagenais(a)gmail.com>
Date: Wed, 6 Mar 2019 15:56:06 -0500
Subject: iio: dac: mcp4725: add missing powerdown bits in store eeprom
When issuing the write DAC register and write eeprom command, the two
powerdown bits (PD0 and PD1) are assumed by the chip to be present in
the bytes sent. Leaving them at 0 implies "powerdown disabled" which is
a different state that the current one. By adding the current state of
the powerdown in the i2c write, the chip will correctly power-on exactly
like as it is at the moment of store_eeprom call.
This is documented in MCP4725's datasheet, FIGURE 6-2: "Write Commands
for DAC Input Register and EEPROM" and MCP4726's datasheet, FIGURE 6-3:
"Write All Memory Command".
Signed-off-by: Jean-Francois Dagenais <jeff.dagenais(a)gmail.com>
Acked-by: Peter Meerwald-Stadler <pmeerw(a)pmeerw.net>
Cc: <Stable(a)vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron(a)huawei.com>
---
drivers/iio/dac/mcp4725.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/iio/dac/mcp4725.c b/drivers/iio/dac/mcp4725.c
index 6d71fd905e29..c701a45469f6 100644
--- a/drivers/iio/dac/mcp4725.c
+++ b/drivers/iio/dac/mcp4725.c
@@ -92,6 +92,7 @@ static ssize_t mcp4725_store_eeprom(struct device *dev,
inoutbuf[0] = 0x60; /* write EEPROM */
inoutbuf[0] |= data->ref_mode << 3;
+ inoutbuf[0] |= data->powerdown ? ((data->powerdown_mode + 1) << 1) : 0;
inoutbuf[1] = data->dac_value >> 4;
inoutbuf[2] = (data->dac_value & 0xf) << 4;
--
2.21.0