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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-lpc18xx-sct.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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 'drivers/pwm/pwm-lpc18xx-sct.c')
-rw-r--r--drivers/pwm/pwm-lpc18xx-sct.c480
1 files changed, 480 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-lpc18xx-sct.c b/drivers/pwm/pwm-lpc18xx-sct.c
new file mode 100644
index 000000000..378e1df94
--- /dev/null
+++ b/drivers/pwm/pwm-lpc18xx-sct.c
@@ -0,0 +1,480 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * NXP LPC18xx State Configurable Timer - Pulse Width Modulator driver
+ *
+ * Copyright (c) 2015 Ariel D'Alessandro <ariel@vanguardiasur.com>
+ *
+ * Notes
+ * =====
+ * NXP LPC18xx provides a State Configurable Timer (SCT) which can be configured
+ * as a Pulse Width Modulator.
+ *
+ * SCT supports 16 outputs, 16 events and 16 registers. Each event will be
+ * triggered when its related register matches the SCT counter value, and it
+ * will set or clear a selected output.
+ *
+ * One of the events is preselected to generate the period, thus the maximum
+ * number of simultaneous channels is limited to 15. Notice that period is
+ * global to all the channels, thus PWM driver will refuse setting different
+ * values to it, unless there's only one channel requested.
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+
+/* LPC18xx SCT registers */
+#define LPC18XX_PWM_CONFIG 0x000
+#define LPC18XX_PWM_CONFIG_UNIFY BIT(0)
+#define LPC18XX_PWM_CONFIG_NORELOAD BIT(7)
+
+#define LPC18XX_PWM_CTRL 0x004
+#define LPC18XX_PWM_CTRL_HALT BIT(2)
+#define LPC18XX_PWM_BIDIR BIT(4)
+#define LPC18XX_PWM_PRE_SHIFT 5
+#define LPC18XX_PWM_PRE_MASK (0xff << LPC18XX_PWM_PRE_SHIFT)
+#define LPC18XX_PWM_PRE(x) (x << LPC18XX_PWM_PRE_SHIFT)
+
+#define LPC18XX_PWM_LIMIT 0x008
+
+#define LPC18XX_PWM_RES_BASE 0x058
+#define LPC18XX_PWM_RES_SHIFT(_ch) (_ch * 2)
+#define LPC18XX_PWM_RES(_ch, _action) (_action << LPC18XX_PWM_RES_SHIFT(_ch))
+#define LPC18XX_PWM_RES_MASK(_ch) (0x3 << LPC18XX_PWM_RES_SHIFT(_ch))
+
+#define LPC18XX_PWM_MATCH_BASE 0x100
+#define LPC18XX_PWM_MATCH(_ch) (LPC18XX_PWM_MATCH_BASE + _ch * 4)
+
+#define LPC18XX_PWM_MATCHREL_BASE 0x200
+#define LPC18XX_PWM_MATCHREL(_ch) (LPC18XX_PWM_MATCHREL_BASE + _ch * 4)
+
+#define LPC18XX_PWM_EVSTATEMSK_BASE 0x300
+#define LPC18XX_PWM_EVSTATEMSK(_ch) (LPC18XX_PWM_EVSTATEMSK_BASE + _ch * 8)
+#define LPC18XX_PWM_EVSTATEMSK_ALL 0xffffffff
+
+#define LPC18XX_PWM_EVCTRL_BASE 0x304
+#define LPC18XX_PWM_EVCTRL(_ev) (LPC18XX_PWM_EVCTRL_BASE + _ev * 8)
+
+#define LPC18XX_PWM_EVCTRL_MATCH(_ch) _ch
+
+#define LPC18XX_PWM_EVCTRL_COMB_SHIFT 12
+#define LPC18XX_PWM_EVCTRL_COMB_MATCH (0x1 << LPC18XX_PWM_EVCTRL_COMB_SHIFT)
+
+#define LPC18XX_PWM_OUTPUTSET_BASE 0x500
+#define LPC18XX_PWM_OUTPUTSET(_ch) (LPC18XX_PWM_OUTPUTSET_BASE + _ch * 8)
+
+#define LPC18XX_PWM_OUTPUTCL_BASE 0x504
+#define LPC18XX_PWM_OUTPUTCL(_ch) (LPC18XX_PWM_OUTPUTCL_BASE + _ch * 8)
+
+/* LPC18xx SCT unified counter */
+#define LPC18XX_PWM_TIMER_MAX 0xffffffff
+
+/* LPC18xx SCT events */
+#define LPC18XX_PWM_EVENT_PERIOD 0
+#define LPC18XX_PWM_EVENT_MAX 16
+
+#define LPC18XX_NUM_PWMS 16
+
+/* SCT conflict resolution */
+enum lpc18xx_pwm_res_action {
+ LPC18XX_PWM_RES_NONE,
+ LPC18XX_PWM_RES_SET,
+ LPC18XX_PWM_RES_CLEAR,
+ LPC18XX_PWM_RES_TOGGLE,
+};
+
+struct lpc18xx_pwm_data {
+ unsigned int duty_event;
+};
+
+struct lpc18xx_pwm_chip {
+ struct device *dev;
+ struct pwm_chip chip;
+ void __iomem *base;
+ struct clk *pwm_clk;
+ unsigned long clk_rate;
+ unsigned int period_ns;
+ unsigned int min_period_ns;
+ u64 max_period_ns;
+ unsigned int period_event;
+ unsigned long event_map;
+ struct mutex res_lock;
+ struct mutex period_lock;
+ struct lpc18xx_pwm_data channeldata[LPC18XX_NUM_PWMS];
+};
+
+static inline struct lpc18xx_pwm_chip *
+to_lpc18xx_pwm_chip(struct pwm_chip *chip)
+{
+ return container_of(chip, struct lpc18xx_pwm_chip, chip);
+}
+
+static inline void lpc18xx_pwm_writel(struct lpc18xx_pwm_chip *lpc18xx_pwm,
+ u32 reg, u32 val)
+{
+ writel(val, lpc18xx_pwm->base + reg);
+}
+
+static inline u32 lpc18xx_pwm_readl(struct lpc18xx_pwm_chip *lpc18xx_pwm,
+ u32 reg)
+{
+ return readl(lpc18xx_pwm->base + reg);
+}
+
+static void lpc18xx_pwm_set_conflict_res(struct lpc18xx_pwm_chip *lpc18xx_pwm,
+ struct pwm_device *pwm,
+ enum lpc18xx_pwm_res_action action)
+{
+ u32 val;
+
+ mutex_lock(&lpc18xx_pwm->res_lock);
+
+ /*
+ * Simultaneous set and clear may happen on an output, that is the case
+ * when duty_ns == period_ns. LPC18xx SCT allows to set a conflict
+ * resolution action to be taken in such a case.
+ */
+ val = lpc18xx_pwm_readl(lpc18xx_pwm, LPC18XX_PWM_RES_BASE);
+ val &= ~LPC18XX_PWM_RES_MASK(pwm->hwpwm);
+ val |= LPC18XX_PWM_RES(pwm->hwpwm, action);
+ lpc18xx_pwm_writel(lpc18xx_pwm, LPC18XX_PWM_RES_BASE, val);
+
+ mutex_unlock(&lpc18xx_pwm->res_lock);
+}
+
+static void lpc18xx_pwm_config_period(struct pwm_chip *chip, u64 period_ns)
+{
+ struct lpc18xx_pwm_chip *lpc18xx_pwm = to_lpc18xx_pwm_chip(chip);
+ u32 val;
+
+ /*
+ * With clk_rate < NSEC_PER_SEC this cannot overflow.
+ * With period_ns < max_period_ns this also fits into an u32.
+ * As period_ns >= min_period_ns = DIV_ROUND_UP(NSEC_PER_SEC, lpc18xx_pwm->clk_rate);
+ * we have val >= 1.
+ */
+ val = mul_u64_u64_div_u64(period_ns, lpc18xx_pwm->clk_rate, NSEC_PER_SEC);
+
+ lpc18xx_pwm_writel(lpc18xx_pwm,
+ LPC18XX_PWM_MATCH(lpc18xx_pwm->period_event),
+ val - 1);
+
+ lpc18xx_pwm_writel(lpc18xx_pwm,
+ LPC18XX_PWM_MATCHREL(lpc18xx_pwm->period_event),
+ val - 1);
+}
+
+static void lpc18xx_pwm_config_duty(struct pwm_chip *chip,
+ struct pwm_device *pwm, u64 duty_ns)
+{
+ struct lpc18xx_pwm_chip *lpc18xx_pwm = to_lpc18xx_pwm_chip(chip);
+ struct lpc18xx_pwm_data *lpc18xx_data = &lpc18xx_pwm->channeldata[pwm->hwpwm];
+ u32 val;
+
+ /*
+ * With clk_rate <= NSEC_PER_SEC this cannot overflow.
+ * With duty_ns <= period_ns < max_period_ns this also fits into an u32.
+ */
+ val = mul_u64_u64_div_u64(duty_ns, lpc18xx_pwm->clk_rate, NSEC_PER_SEC);
+
+ lpc18xx_pwm_writel(lpc18xx_pwm,
+ LPC18XX_PWM_MATCH(lpc18xx_data->duty_event),
+ val);
+
+ lpc18xx_pwm_writel(lpc18xx_pwm,
+ LPC18XX_PWM_MATCHREL(lpc18xx_data->duty_event),
+ val);
+}
+
+static int lpc18xx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+ int duty_ns, int period_ns)
+{
+ struct lpc18xx_pwm_chip *lpc18xx_pwm = to_lpc18xx_pwm_chip(chip);
+ int requested_events, i;
+
+ if (period_ns < lpc18xx_pwm->min_period_ns ||
+ period_ns > lpc18xx_pwm->max_period_ns) {
+ dev_err(chip->dev, "period %d not in range\n", period_ns);
+ return -ERANGE;
+ }
+
+ mutex_lock(&lpc18xx_pwm->period_lock);
+
+ requested_events = bitmap_weight(&lpc18xx_pwm->event_map,
+ LPC18XX_PWM_EVENT_MAX);
+
+ /*
+ * The PWM supports only a single period for all PWM channels.
+ * Once the period is set, it can only be changed if no more than one
+ * channel is requested at that moment.
+ */
+ if (requested_events > 2 && lpc18xx_pwm->period_ns != period_ns &&
+ lpc18xx_pwm->period_ns) {
+ dev_err(chip->dev, "conflicting period requested for PWM %u\n",
+ pwm->hwpwm);
+ mutex_unlock(&lpc18xx_pwm->period_lock);
+ return -EBUSY;
+ }
+
+ if ((requested_events <= 2 && lpc18xx_pwm->period_ns != period_ns) ||
+ !lpc18xx_pwm->period_ns) {
+ lpc18xx_pwm->period_ns = period_ns;
+ for (i = 0; i < chip->npwm; i++)
+ pwm_set_period(&chip->pwms[i], period_ns);
+ lpc18xx_pwm_config_period(chip, period_ns);
+ }
+
+ mutex_unlock(&lpc18xx_pwm->period_lock);
+
+ lpc18xx_pwm_config_duty(chip, pwm, duty_ns);
+
+ return 0;
+}
+
+static int lpc18xx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm, enum pwm_polarity polarity)
+{
+ struct lpc18xx_pwm_chip *lpc18xx_pwm = to_lpc18xx_pwm_chip(chip);
+ struct lpc18xx_pwm_data *lpc18xx_data = &lpc18xx_pwm->channeldata[pwm->hwpwm];
+ enum lpc18xx_pwm_res_action res_action;
+ unsigned int set_event, clear_event;
+
+ lpc18xx_pwm_writel(lpc18xx_pwm,
+ LPC18XX_PWM_EVCTRL(lpc18xx_data->duty_event),
+ LPC18XX_PWM_EVCTRL_MATCH(lpc18xx_data->duty_event) |
+ LPC18XX_PWM_EVCTRL_COMB_MATCH);
+
+ lpc18xx_pwm_writel(lpc18xx_pwm,
+ LPC18XX_PWM_EVSTATEMSK(lpc18xx_data->duty_event),
+ LPC18XX_PWM_EVSTATEMSK_ALL);
+
+ if (polarity == PWM_POLARITY_NORMAL) {
+ set_event = lpc18xx_pwm->period_event;
+ clear_event = lpc18xx_data->duty_event;
+ res_action = LPC18XX_PWM_RES_SET;
+ } else {
+ set_event = lpc18xx_data->duty_event;
+ clear_event = lpc18xx_pwm->period_event;
+ res_action = LPC18XX_PWM_RES_CLEAR;
+ }
+
+ lpc18xx_pwm_writel(lpc18xx_pwm, LPC18XX_PWM_OUTPUTSET(pwm->hwpwm),
+ BIT(set_event));
+ lpc18xx_pwm_writel(lpc18xx_pwm, LPC18XX_PWM_OUTPUTCL(pwm->hwpwm),
+ BIT(clear_event));
+ lpc18xx_pwm_set_conflict_res(lpc18xx_pwm, pwm, res_action);
+
+ return 0;
+}
+
+static void lpc18xx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct lpc18xx_pwm_chip *lpc18xx_pwm = to_lpc18xx_pwm_chip(chip);
+ struct lpc18xx_pwm_data *lpc18xx_data = &lpc18xx_pwm->channeldata[pwm->hwpwm];
+
+ lpc18xx_pwm_writel(lpc18xx_pwm,
+ LPC18XX_PWM_EVCTRL(lpc18xx_data->duty_event), 0);
+ lpc18xx_pwm_writel(lpc18xx_pwm, LPC18XX_PWM_OUTPUTSET(pwm->hwpwm), 0);
+ lpc18xx_pwm_writel(lpc18xx_pwm, LPC18XX_PWM_OUTPUTCL(pwm->hwpwm), 0);
+}
+
+static int lpc18xx_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct lpc18xx_pwm_chip *lpc18xx_pwm = to_lpc18xx_pwm_chip(chip);
+ struct lpc18xx_pwm_data *lpc18xx_data = &lpc18xx_pwm->channeldata[pwm->hwpwm];
+ unsigned long event;
+
+ event = find_first_zero_bit(&lpc18xx_pwm->event_map,
+ LPC18XX_PWM_EVENT_MAX);
+
+ if (event >= LPC18XX_PWM_EVENT_MAX) {
+ dev_err(lpc18xx_pwm->dev,
+ "maximum number of simultaneous channels reached\n");
+ return -EBUSY;
+ }
+
+ set_bit(event, &lpc18xx_pwm->event_map);
+ lpc18xx_data->duty_event = event;
+
+ return 0;
+}
+
+static void lpc18xx_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct lpc18xx_pwm_chip *lpc18xx_pwm = to_lpc18xx_pwm_chip(chip);
+ struct lpc18xx_pwm_data *lpc18xx_data = &lpc18xx_pwm->channeldata[pwm->hwpwm];
+
+ clear_bit(lpc18xx_data->duty_event, &lpc18xx_pwm->event_map);
+}
+
+static int lpc18xx_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ const struct pwm_state *state)
+{
+ int err;
+ bool enabled = pwm->state.enabled;
+
+ if (state->polarity != pwm->state.polarity && pwm->state.enabled) {
+ lpc18xx_pwm_disable(chip, pwm);
+ enabled = false;
+ }
+
+ if (!state->enabled) {
+ if (enabled)
+ lpc18xx_pwm_disable(chip, pwm);
+
+ return 0;
+ }
+
+ err = lpc18xx_pwm_config(pwm->chip, pwm, state->duty_cycle, state->period);
+ if (err)
+ return err;
+
+ if (!enabled)
+ err = lpc18xx_pwm_enable(chip, pwm, state->polarity);
+
+ return err;
+}
+static const struct pwm_ops lpc18xx_pwm_ops = {
+ .apply = lpc18xx_pwm_apply,
+ .request = lpc18xx_pwm_request,
+ .free = lpc18xx_pwm_free,
+ .owner = THIS_MODULE,
+};
+
+static const struct of_device_id lpc18xx_pwm_of_match[] = {
+ { .compatible = "nxp,lpc1850-sct-pwm" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, lpc18xx_pwm_of_match);
+
+static int lpc18xx_pwm_probe(struct platform_device *pdev)
+{
+ struct lpc18xx_pwm_chip *lpc18xx_pwm;
+ int ret;
+ u64 val;
+
+ lpc18xx_pwm = devm_kzalloc(&pdev->dev, sizeof(*lpc18xx_pwm),
+ GFP_KERNEL);
+ if (!lpc18xx_pwm)
+ return -ENOMEM;
+
+ lpc18xx_pwm->dev = &pdev->dev;
+
+ lpc18xx_pwm->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(lpc18xx_pwm->base))
+ return PTR_ERR(lpc18xx_pwm->base);
+
+ lpc18xx_pwm->pwm_clk = devm_clk_get(&pdev->dev, "pwm");
+ if (IS_ERR(lpc18xx_pwm->pwm_clk))
+ return dev_err_probe(&pdev->dev, PTR_ERR(lpc18xx_pwm->pwm_clk),
+ "failed to get pwm clock\n");
+
+ ret = clk_prepare_enable(lpc18xx_pwm->pwm_clk);
+ if (ret < 0)
+ return dev_err_probe(&pdev->dev, ret,
+ "could not prepare or enable pwm clock\n");
+
+ lpc18xx_pwm->clk_rate = clk_get_rate(lpc18xx_pwm->pwm_clk);
+ if (!lpc18xx_pwm->clk_rate) {
+ ret = dev_err_probe(&pdev->dev,
+ -EINVAL, "pwm clock has no frequency\n");
+ goto disable_pwmclk;
+ }
+
+ /*
+ * If clkrate is too fast, the calculations in .apply() might overflow.
+ */
+ if (lpc18xx_pwm->clk_rate > NSEC_PER_SEC) {
+ ret = dev_err_probe(&pdev->dev, -EINVAL, "pwm clock to fast\n");
+ goto disable_pwmclk;
+ }
+
+ mutex_init(&lpc18xx_pwm->res_lock);
+ mutex_init(&lpc18xx_pwm->period_lock);
+
+ lpc18xx_pwm->max_period_ns =
+ mul_u64_u64_div_u64(NSEC_PER_SEC, LPC18XX_PWM_TIMER_MAX, lpc18xx_pwm->clk_rate);
+
+ lpc18xx_pwm->min_period_ns = DIV_ROUND_UP(NSEC_PER_SEC,
+ lpc18xx_pwm->clk_rate);
+
+ lpc18xx_pwm->chip.dev = &pdev->dev;
+ lpc18xx_pwm->chip.ops = &lpc18xx_pwm_ops;
+ lpc18xx_pwm->chip.npwm = LPC18XX_NUM_PWMS;
+
+ /* SCT counter must be in unify (32 bit) mode */
+ lpc18xx_pwm_writel(lpc18xx_pwm, LPC18XX_PWM_CONFIG,
+ LPC18XX_PWM_CONFIG_UNIFY);
+
+ /*
+ * Everytime the timer counter reaches the period value, the related
+ * event will be triggered and the counter reset to 0.
+ */
+ set_bit(LPC18XX_PWM_EVENT_PERIOD, &lpc18xx_pwm->event_map);
+ lpc18xx_pwm->period_event = LPC18XX_PWM_EVENT_PERIOD;
+
+ lpc18xx_pwm_writel(lpc18xx_pwm,
+ LPC18XX_PWM_EVSTATEMSK(lpc18xx_pwm->period_event),
+ LPC18XX_PWM_EVSTATEMSK_ALL);
+
+ val = LPC18XX_PWM_EVCTRL_MATCH(lpc18xx_pwm->period_event) |
+ LPC18XX_PWM_EVCTRL_COMB_MATCH;
+ lpc18xx_pwm_writel(lpc18xx_pwm,
+ LPC18XX_PWM_EVCTRL(lpc18xx_pwm->period_event), val);
+
+ lpc18xx_pwm_writel(lpc18xx_pwm, LPC18XX_PWM_LIMIT,
+ BIT(lpc18xx_pwm->period_event));
+
+ val = lpc18xx_pwm_readl(lpc18xx_pwm, LPC18XX_PWM_CTRL);
+ val &= ~LPC18XX_PWM_BIDIR;
+ val &= ~LPC18XX_PWM_CTRL_HALT;
+ val &= ~LPC18XX_PWM_PRE_MASK;
+ val |= LPC18XX_PWM_PRE(0);
+ lpc18xx_pwm_writel(lpc18xx_pwm, LPC18XX_PWM_CTRL, val);
+
+ ret = pwmchip_add(&lpc18xx_pwm->chip);
+ if (ret < 0) {
+ dev_err_probe(&pdev->dev, ret, "pwmchip_add failed\n");
+ goto disable_pwmclk;
+ }
+
+ platform_set_drvdata(pdev, lpc18xx_pwm);
+
+ return 0;
+
+disable_pwmclk:
+ clk_disable_unprepare(lpc18xx_pwm->pwm_clk);
+ return ret;
+}
+
+static int lpc18xx_pwm_remove(struct platform_device *pdev)
+{
+ struct lpc18xx_pwm_chip *lpc18xx_pwm = platform_get_drvdata(pdev);
+ u32 val;
+
+ pwmchip_remove(&lpc18xx_pwm->chip);
+
+ val = lpc18xx_pwm_readl(lpc18xx_pwm, LPC18XX_PWM_CTRL);
+ lpc18xx_pwm_writel(lpc18xx_pwm, LPC18XX_PWM_CTRL,
+ val | LPC18XX_PWM_CTRL_HALT);
+
+ clk_disable_unprepare(lpc18xx_pwm->pwm_clk);
+
+ return 0;
+}
+
+static struct platform_driver lpc18xx_pwm_driver = {
+ .driver = {
+ .name = "lpc18xx-sct-pwm",
+ .of_match_table = lpc18xx_pwm_of_match,
+ },
+ .probe = lpc18xx_pwm_probe,
+ .remove = lpc18xx_pwm_remove,
+};
+module_platform_driver(lpc18xx_pwm_driver);
+
+MODULE_AUTHOR("Ariel D'Alessandro <ariel@vanguardiasur.com.ar>");
+MODULE_DESCRIPTION("NXP LPC18xx PWM driver");
+MODULE_LICENSE("GPL v2");