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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/pwm/pwm-samsung.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to '')
-rw-r--r--drivers/pwm/pwm-samsung.c685
1 files changed, 685 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-samsung.c b/drivers/pwm/pwm-samsung.c
new file mode 100644
index 000000000..9c5b4f515
--- /dev/null
+++ b/drivers/pwm/pwm-samsung.c
@@ -0,0 +1,685 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2007 Ben Dooks
+ * Copyright (c) 2008 Simtec Electronics
+ * Ben Dooks <ben@simtec.co.uk>, <ben-linux@fluff.org>
+ * Copyright (c) 2013 Tomasz Figa <tomasz.figa@gmail.com>
+ * Copyright (c) 2017 Samsung Electronics Co., Ltd.
+ *
+ * PWM driver for Samsung SoCs
+ */
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/export.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/time.h>
+
+/* For struct samsung_timer_variant and samsung_pwm_lock. */
+#include <clocksource/samsung_pwm.h>
+
+#define REG_TCFG0 0x00
+#define REG_TCFG1 0x04
+#define REG_TCON 0x08
+
+#define REG_TCNTB(chan) (0x0c + ((chan) * 0xc))
+#define REG_TCMPB(chan) (0x10 + ((chan) * 0xc))
+
+#define TCFG0_PRESCALER_MASK 0xff
+#define TCFG0_PRESCALER1_SHIFT 8
+
+#define TCFG1_MUX_MASK 0xf
+#define TCFG1_SHIFT(chan) (4 * (chan))
+
+/*
+ * Each channel occupies 4 bits in TCON register, but there is a gap of 4
+ * bits (one channel) after channel 0, so channels have different numbering
+ * when accessing TCON register. See to_tcon_channel() function.
+ *
+ * In addition, the location of autoreload bit for channel 4 (TCON channel 5)
+ * in its set of bits is 2 as opposed to 3 for other channels.
+ */
+#define TCON_START(chan) BIT(4 * (chan) + 0)
+#define TCON_MANUALUPDATE(chan) BIT(4 * (chan) + 1)
+#define TCON_INVERT(chan) BIT(4 * (chan) + 2)
+#define _TCON_AUTORELOAD(chan) BIT(4 * (chan) + 3)
+#define _TCON_AUTORELOAD4(chan) BIT(4 * (chan) + 2)
+#define TCON_AUTORELOAD(chan) \
+ ((chan < 5) ? _TCON_AUTORELOAD(chan) : _TCON_AUTORELOAD4(chan))
+
+/**
+ * struct samsung_pwm_channel - private data of PWM channel
+ * @period_ns: current period in nanoseconds programmed to the hardware
+ * @duty_ns: current duty time in nanoseconds programmed to the hardware
+ * @tin_ns: time of one timer tick in nanoseconds with current timer rate
+ */
+struct samsung_pwm_channel {
+ u32 period_ns;
+ u32 duty_ns;
+ u32 tin_ns;
+};
+
+/**
+ * struct samsung_pwm_chip - private data of PWM chip
+ * @chip: generic PWM chip
+ * @variant: local copy of hardware variant data
+ * @inverter_mask: inverter status for all channels - one bit per channel
+ * @disabled_mask: disabled status for all channels - one bit per channel
+ * @base: base address of mapped PWM registers
+ * @base_clk: base clock used to drive the timers
+ * @tclk0: external clock 0 (can be ERR_PTR if not present)
+ * @tclk1: external clock 1 (can be ERR_PTR if not present)
+ */
+struct samsung_pwm_chip {
+ struct pwm_chip chip;
+ struct samsung_pwm_variant variant;
+ u8 inverter_mask;
+ u8 disabled_mask;
+
+ void __iomem *base;
+ struct clk *base_clk;
+ struct clk *tclk0;
+ struct clk *tclk1;
+};
+
+#ifndef CONFIG_CLKSRC_SAMSUNG_PWM
+/*
+ * PWM block is shared between pwm-samsung and samsung_pwm_timer drivers
+ * and some registers need access synchronization. If both drivers are
+ * compiled in, the spinlock is defined in the clocksource driver,
+ * otherwise following definition is used.
+ *
+ * Currently we do not need any more complex synchronization method
+ * because all the supported SoCs contain only one instance of the PWM
+ * IP. Should this change, both drivers will need to be modified to
+ * properly synchronize accesses to particular instances.
+ */
+static DEFINE_SPINLOCK(samsung_pwm_lock);
+#endif
+
+static inline
+struct samsung_pwm_chip *to_samsung_pwm_chip(struct pwm_chip *chip)
+{
+ return container_of(chip, struct samsung_pwm_chip, chip);
+}
+
+static inline unsigned int to_tcon_channel(unsigned int channel)
+{
+ /* TCON register has a gap of 4 bits (1 channel) after channel 0 */
+ return (channel == 0) ? 0 : (channel + 1);
+}
+
+static void __pwm_samsung_manual_update(struct samsung_pwm_chip *chip,
+ struct pwm_device *pwm)
+{
+ unsigned int tcon_chan = to_tcon_channel(pwm->hwpwm);
+ u32 tcon;
+
+ tcon = readl(chip->base + REG_TCON);
+ tcon |= TCON_MANUALUPDATE(tcon_chan);
+ writel(tcon, chip->base + REG_TCON);
+
+ tcon &= ~TCON_MANUALUPDATE(tcon_chan);
+ writel(tcon, chip->base + REG_TCON);
+}
+
+static void pwm_samsung_set_divisor(struct samsung_pwm_chip *pwm,
+ unsigned int channel, u8 divisor)
+{
+ u8 shift = TCFG1_SHIFT(channel);
+ unsigned long flags;
+ u32 reg;
+ u8 bits;
+
+ bits = (fls(divisor) - 1) - pwm->variant.div_base;
+
+ spin_lock_irqsave(&samsung_pwm_lock, flags);
+
+ reg = readl(pwm->base + REG_TCFG1);
+ reg &= ~(TCFG1_MUX_MASK << shift);
+ reg |= bits << shift;
+ writel(reg, pwm->base + REG_TCFG1);
+
+ spin_unlock_irqrestore(&samsung_pwm_lock, flags);
+}
+
+static int pwm_samsung_is_tdiv(struct samsung_pwm_chip *chip, unsigned int chan)
+{
+ struct samsung_pwm_variant *variant = &chip->variant;
+ u32 reg;
+
+ reg = readl(chip->base + REG_TCFG1);
+ reg >>= TCFG1_SHIFT(chan);
+ reg &= TCFG1_MUX_MASK;
+
+ return (BIT(reg) & variant->tclk_mask) == 0;
+}
+
+static unsigned long pwm_samsung_get_tin_rate(struct samsung_pwm_chip *chip,
+ unsigned int chan)
+{
+ unsigned long rate;
+ u32 reg;
+
+ rate = clk_get_rate(chip->base_clk);
+
+ reg = readl(chip->base + REG_TCFG0);
+ if (chan >= 2)
+ reg >>= TCFG0_PRESCALER1_SHIFT;
+ reg &= TCFG0_PRESCALER_MASK;
+
+ return rate / (reg + 1);
+}
+
+static unsigned long pwm_samsung_calc_tin(struct samsung_pwm_chip *chip,
+ unsigned int chan, unsigned long freq)
+{
+ struct samsung_pwm_variant *variant = &chip->variant;
+ unsigned long rate;
+ struct clk *clk;
+ u8 div;
+
+ if (!pwm_samsung_is_tdiv(chip, chan)) {
+ clk = (chan < 2) ? chip->tclk0 : chip->tclk1;
+ if (!IS_ERR(clk)) {
+ rate = clk_get_rate(clk);
+ if (rate)
+ return rate;
+ }
+
+ dev_warn(chip->chip.dev,
+ "tclk of PWM %d is inoperational, using tdiv\n", chan);
+ }
+
+ rate = pwm_samsung_get_tin_rate(chip, chan);
+ dev_dbg(chip->chip.dev, "tin parent at %lu\n", rate);
+
+ /*
+ * Compare minimum PWM frequency that can be achieved with possible
+ * divider settings and choose the lowest divisor that can generate
+ * frequencies lower than requested.
+ */
+ if (variant->bits < 32) {
+ /* Only for s3c24xx */
+ for (div = variant->div_base; div < 4; ++div)
+ if ((rate >> (variant->bits + div)) < freq)
+ break;
+ } else {
+ /*
+ * Other variants have enough counter bits to generate any
+ * requested rate, so no need to check higher divisors.
+ */
+ div = variant->div_base;
+ }
+
+ pwm_samsung_set_divisor(chip, chan, BIT(div));
+
+ return rate >> div;
+}
+
+static int pwm_samsung_request(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip);
+ struct samsung_pwm_channel *our_chan;
+
+ if (!(our_chip->variant.output_mask & BIT(pwm->hwpwm))) {
+ dev_warn(chip->dev,
+ "tried to request PWM channel %d without output\n",
+ pwm->hwpwm);
+ return -EINVAL;
+ }
+
+ our_chan = kzalloc(sizeof(*our_chan), GFP_KERNEL);
+ if (!our_chan)
+ return -ENOMEM;
+
+ pwm_set_chip_data(pwm, our_chan);
+
+ return 0;
+}
+
+static void pwm_samsung_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ kfree(pwm_get_chip_data(pwm));
+}
+
+static int pwm_samsung_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip);
+ unsigned int tcon_chan = to_tcon_channel(pwm->hwpwm);
+ unsigned long flags;
+ u32 tcon;
+
+ spin_lock_irqsave(&samsung_pwm_lock, flags);
+
+ tcon = readl(our_chip->base + REG_TCON);
+
+ tcon &= ~TCON_START(tcon_chan);
+ tcon |= TCON_MANUALUPDATE(tcon_chan);
+ writel(tcon, our_chip->base + REG_TCON);
+
+ tcon &= ~TCON_MANUALUPDATE(tcon_chan);
+ tcon |= TCON_START(tcon_chan) | TCON_AUTORELOAD(tcon_chan);
+ writel(tcon, our_chip->base + REG_TCON);
+
+ our_chip->disabled_mask &= ~BIT(pwm->hwpwm);
+
+ spin_unlock_irqrestore(&samsung_pwm_lock, flags);
+
+ return 0;
+}
+
+static void pwm_samsung_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip);
+ unsigned int tcon_chan = to_tcon_channel(pwm->hwpwm);
+ unsigned long flags;
+ u32 tcon;
+
+ spin_lock_irqsave(&samsung_pwm_lock, flags);
+
+ tcon = readl(our_chip->base + REG_TCON);
+ tcon &= ~TCON_AUTORELOAD(tcon_chan);
+ writel(tcon, our_chip->base + REG_TCON);
+
+ /*
+ * In case the PWM is at 100% duty cycle, force a manual
+ * update to prevent the signal from staying high.
+ */
+ if (readl(our_chip->base + REG_TCMPB(pwm->hwpwm)) == (u32)-1U)
+ __pwm_samsung_manual_update(our_chip, pwm);
+
+ our_chip->disabled_mask |= BIT(pwm->hwpwm);
+
+ spin_unlock_irqrestore(&samsung_pwm_lock, flags);
+}
+
+static void pwm_samsung_manual_update(struct samsung_pwm_chip *chip,
+ struct pwm_device *pwm)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&samsung_pwm_lock, flags);
+
+ __pwm_samsung_manual_update(chip, pwm);
+
+ spin_unlock_irqrestore(&samsung_pwm_lock, flags);
+}
+
+static int __pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,
+ int duty_ns, int period_ns, bool force_period)
+{
+ struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip);
+ struct samsung_pwm_channel *chan = pwm_get_chip_data(pwm);
+ u32 tin_ns = chan->tin_ns, tcnt, tcmp, oldtcmp;
+
+ tcnt = readl(our_chip->base + REG_TCNTB(pwm->hwpwm));
+ oldtcmp = readl(our_chip->base + REG_TCMPB(pwm->hwpwm));
+
+ /* We need tick count for calculation, not last tick. */
+ ++tcnt;
+
+ /* Check to see if we are changing the clock rate of the PWM. */
+ if (chan->period_ns != period_ns || force_period) {
+ unsigned long tin_rate;
+ u32 period;
+
+ period = NSEC_PER_SEC / period_ns;
+
+ dev_dbg(our_chip->chip.dev, "duty_ns=%d, period_ns=%d (%u)\n",
+ duty_ns, period_ns, period);
+
+ tin_rate = pwm_samsung_calc_tin(our_chip, pwm->hwpwm, period);
+
+ dev_dbg(our_chip->chip.dev, "tin_rate=%lu\n", tin_rate);
+
+ tin_ns = NSEC_PER_SEC / tin_rate;
+ tcnt = period_ns / tin_ns;
+ }
+
+ /* Period is too short. */
+ if (tcnt <= 1)
+ return -ERANGE;
+
+ /* Note that counters count down. */
+ tcmp = duty_ns / tin_ns;
+
+ /* 0% duty is not available */
+ if (!tcmp)
+ ++tcmp;
+
+ tcmp = tcnt - tcmp;
+
+ /* Decrement to get tick numbers, instead of tick counts. */
+ --tcnt;
+ /* -1UL will give 100% duty. */
+ --tcmp;
+
+ dev_dbg(our_chip->chip.dev,
+ "tin_ns=%u, tcmp=%u/%u\n", tin_ns, tcmp, tcnt);
+
+ /* Update PWM registers. */
+ writel(tcnt, our_chip->base + REG_TCNTB(pwm->hwpwm));
+ writel(tcmp, our_chip->base + REG_TCMPB(pwm->hwpwm));
+
+ /*
+ * In case the PWM is currently at 100% duty cycle, force a manual
+ * update to prevent the signal staying high if the PWM is disabled
+ * shortly afer this update (before it autoreloaded the new values).
+ */
+ if (oldtcmp == (u32) -1) {
+ dev_dbg(our_chip->chip.dev, "Forcing manual update");
+ pwm_samsung_manual_update(our_chip, pwm);
+ }
+
+ chan->period_ns = period_ns;
+ chan->tin_ns = tin_ns;
+ chan->duty_ns = duty_ns;
+
+ return 0;
+}
+
+static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,
+ int duty_ns, int period_ns)
+{
+ return __pwm_samsung_config(chip, pwm, duty_ns, period_ns, false);
+}
+
+static void pwm_samsung_set_invert(struct samsung_pwm_chip *chip,
+ unsigned int channel, bool invert)
+{
+ unsigned int tcon_chan = to_tcon_channel(channel);
+ unsigned long flags;
+ u32 tcon;
+
+ spin_lock_irqsave(&samsung_pwm_lock, flags);
+
+ tcon = readl(chip->base + REG_TCON);
+
+ if (invert) {
+ chip->inverter_mask |= BIT(channel);
+ tcon |= TCON_INVERT(tcon_chan);
+ } else {
+ chip->inverter_mask &= ~BIT(channel);
+ tcon &= ~TCON_INVERT(tcon_chan);
+ }
+
+ writel(tcon, chip->base + REG_TCON);
+
+ spin_unlock_irqrestore(&samsung_pwm_lock, flags);
+}
+
+static int pwm_samsung_set_polarity(struct pwm_chip *chip,
+ struct pwm_device *pwm,
+ enum pwm_polarity polarity)
+{
+ struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip);
+ bool invert = (polarity == PWM_POLARITY_NORMAL);
+
+ /* Inverted means normal in the hardware. */
+ pwm_samsung_set_invert(our_chip, pwm->hwpwm, invert);
+
+ return 0;
+}
+
+static int pwm_samsung_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ const struct pwm_state *state)
+{
+ int err, enabled = pwm->state.enabled;
+
+ if (state->polarity != pwm->state.polarity) {
+ if (enabled) {
+ pwm_samsung_disable(chip, pwm);
+ enabled = false;
+ }
+
+ err = pwm_samsung_set_polarity(chip, pwm, state->polarity);
+ if (err)
+ return err;
+ }
+
+ if (!state->enabled) {
+ if (enabled)
+ pwm_samsung_disable(chip, pwm);
+
+ return 0;
+ }
+
+ /*
+ * We currently avoid using 64bit arithmetic by using the
+ * fact that anything faster than 1Hz is easily representable
+ * by 32bits.
+ */
+ if (state->period > NSEC_PER_SEC)
+ return -ERANGE;
+
+ err = pwm_samsung_config(chip, pwm, state->duty_cycle, state->period);
+ if (err)
+ return err;
+
+ if (!pwm->state.enabled)
+ err = pwm_samsung_enable(chip, pwm);
+
+ return err;
+}
+
+static const struct pwm_ops pwm_samsung_ops = {
+ .request = pwm_samsung_request,
+ .free = pwm_samsung_free,
+ .apply = pwm_samsung_apply,
+ .owner = THIS_MODULE,
+};
+
+#ifdef CONFIG_OF
+static const struct samsung_pwm_variant s3c24xx_variant = {
+ .bits = 16,
+ .div_base = 1,
+ .has_tint_cstat = false,
+ .tclk_mask = BIT(4),
+};
+
+static const struct samsung_pwm_variant s3c64xx_variant = {
+ .bits = 32,
+ .div_base = 0,
+ .has_tint_cstat = true,
+ .tclk_mask = BIT(7) | BIT(6) | BIT(5),
+};
+
+static const struct samsung_pwm_variant s5p64x0_variant = {
+ .bits = 32,
+ .div_base = 0,
+ .has_tint_cstat = true,
+ .tclk_mask = 0,
+};
+
+static const struct samsung_pwm_variant s5pc100_variant = {
+ .bits = 32,
+ .div_base = 0,
+ .has_tint_cstat = true,
+ .tclk_mask = BIT(5),
+};
+
+static const struct of_device_id samsung_pwm_matches[] = {
+ { .compatible = "samsung,s3c2410-pwm", .data = &s3c24xx_variant },
+ { .compatible = "samsung,s3c6400-pwm", .data = &s3c64xx_variant },
+ { .compatible = "samsung,s5p6440-pwm", .data = &s5p64x0_variant },
+ { .compatible = "samsung,s5pc100-pwm", .data = &s5pc100_variant },
+ { .compatible = "samsung,exynos4210-pwm", .data = &s5p64x0_variant },
+ {},
+};
+MODULE_DEVICE_TABLE(of, samsung_pwm_matches);
+
+static int pwm_samsung_parse_dt(struct samsung_pwm_chip *chip)
+{
+ struct device_node *np = chip->chip.dev->of_node;
+ const struct of_device_id *match;
+ struct property *prop;
+ const __be32 *cur;
+ u32 val;
+
+ match = of_match_node(samsung_pwm_matches, np);
+ if (!match)
+ return -ENODEV;
+
+ memcpy(&chip->variant, match->data, sizeof(chip->variant));
+
+ of_property_for_each_u32(np, "samsung,pwm-outputs", prop, cur, val) {
+ if (val >= SAMSUNG_PWM_NUM) {
+ dev_err(chip->chip.dev,
+ "%s: invalid channel index in samsung,pwm-outputs property\n",
+ __func__);
+ continue;
+ }
+ chip->variant.output_mask |= BIT(val);
+ }
+
+ return 0;
+}
+#else
+static int pwm_samsung_parse_dt(struct samsung_pwm_chip *chip)
+{
+ return -ENODEV;
+}
+#endif
+
+static int pwm_samsung_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct samsung_pwm_chip *chip;
+ unsigned int chan;
+ int ret;
+
+ chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
+ if (chip == NULL)
+ return -ENOMEM;
+
+ chip->chip.dev = &pdev->dev;
+ chip->chip.ops = &pwm_samsung_ops;
+ chip->chip.npwm = SAMSUNG_PWM_NUM;
+ chip->inverter_mask = BIT(SAMSUNG_PWM_NUM) - 1;
+
+ if (IS_ENABLED(CONFIG_OF) && pdev->dev.of_node) {
+ ret = pwm_samsung_parse_dt(chip);
+ if (ret)
+ return ret;
+ } else {
+ if (!pdev->dev.platform_data) {
+ dev_err(&pdev->dev, "no platform data specified\n");
+ return -EINVAL;
+ }
+
+ memcpy(&chip->variant, pdev->dev.platform_data,
+ sizeof(chip->variant));
+ }
+
+ chip->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(chip->base))
+ return PTR_ERR(chip->base);
+
+ chip->base_clk = devm_clk_get(&pdev->dev, "timers");
+ if (IS_ERR(chip->base_clk)) {
+ dev_err(dev, "failed to get timer base clk\n");
+ return PTR_ERR(chip->base_clk);
+ }
+
+ ret = clk_prepare_enable(chip->base_clk);
+ if (ret < 0) {
+ dev_err(dev, "failed to enable base clock\n");
+ return ret;
+ }
+
+ for (chan = 0; chan < SAMSUNG_PWM_NUM; ++chan)
+ if (chip->variant.output_mask & BIT(chan))
+ pwm_samsung_set_invert(chip, chan, true);
+
+ /* Following clocks are optional. */
+ chip->tclk0 = devm_clk_get(&pdev->dev, "pwm-tclk0");
+ chip->tclk1 = devm_clk_get(&pdev->dev, "pwm-tclk1");
+
+ platform_set_drvdata(pdev, chip);
+
+ ret = pwmchip_add(&chip->chip);
+ if (ret < 0) {
+ dev_err(dev, "failed to register PWM chip\n");
+ clk_disable_unprepare(chip->base_clk);
+ return ret;
+ }
+
+ dev_dbg(dev, "base_clk at %lu, tclk0 at %lu, tclk1 at %lu\n",
+ clk_get_rate(chip->base_clk),
+ !IS_ERR(chip->tclk0) ? clk_get_rate(chip->tclk0) : 0,
+ !IS_ERR(chip->tclk1) ? clk_get_rate(chip->tclk1) : 0);
+
+ return 0;
+}
+
+static int pwm_samsung_remove(struct platform_device *pdev)
+{
+ struct samsung_pwm_chip *chip = platform_get_drvdata(pdev);
+
+ pwmchip_remove(&chip->chip);
+
+ clk_disable_unprepare(chip->base_clk);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int pwm_samsung_resume(struct device *dev)
+{
+ struct samsung_pwm_chip *our_chip = dev_get_drvdata(dev);
+ struct pwm_chip *chip = &our_chip->chip;
+ unsigned int i;
+
+ for (i = 0; i < SAMSUNG_PWM_NUM; i++) {
+ struct pwm_device *pwm = &chip->pwms[i];
+ struct samsung_pwm_channel *chan = pwm_get_chip_data(pwm);
+
+ if (!chan)
+ continue;
+
+ if (our_chip->variant.output_mask & BIT(i))
+ pwm_samsung_set_invert(our_chip, i,
+ our_chip->inverter_mask & BIT(i));
+
+ if (chan->period_ns) {
+ __pwm_samsung_config(chip, pwm, chan->duty_ns,
+ chan->period_ns, true);
+ /* needed to make PWM disable work on Odroid-XU3 */
+ pwm_samsung_manual_update(our_chip, pwm);
+ }
+
+ if (our_chip->disabled_mask & BIT(i))
+ pwm_samsung_disable(chip, pwm);
+ else
+ pwm_samsung_enable(chip, pwm);
+ }
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(pwm_samsung_pm_ops, NULL, pwm_samsung_resume);
+
+static struct platform_driver pwm_samsung_driver = {
+ .driver = {
+ .name = "samsung-pwm",
+ .pm = &pwm_samsung_pm_ops,
+ .of_match_table = of_match_ptr(samsung_pwm_matches),
+ },
+ .probe = pwm_samsung_probe,
+ .remove = pwm_samsung_remove,
+};
+module_platform_driver(pwm_samsung_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Tomasz Figa <tomasz.figa@gmail.com>");
+MODULE_ALIAS("platform:samsung-pwm");