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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/rtc/rtc-m48t59.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/rtc/rtc-m48t59.c488
1 files changed, 488 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-m48t59.c b/drivers/rtc/rtc-m48t59.c
new file mode 100644
index 000000000..f0f6b9b6d
--- /dev/null
+++ b/drivers/rtc/rtc-m48t59.c
@@ -0,0 +1,488 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ST M48T59 RTC driver
+ *
+ * Copyright (c) 2007 Wind River Systems, Inc.
+ *
+ * Author: Mark Zhan <rongkai.zhan@windriver.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+#include <linux/rtc/m48t59.h>
+#include <linux/bcd.h>
+#include <linux/slab.h>
+
+#ifndef NO_IRQ
+#define NO_IRQ (-1)
+#endif
+
+#define M48T59_READ(reg) (pdata->read_byte(dev, pdata->offset + reg))
+#define M48T59_WRITE(val, reg) \
+ (pdata->write_byte(dev, pdata->offset + reg, val))
+
+#define M48T59_SET_BITS(mask, reg) \
+ M48T59_WRITE((M48T59_READ(reg) | (mask)), (reg))
+#define M48T59_CLEAR_BITS(mask, reg) \
+ M48T59_WRITE((M48T59_READ(reg) & ~(mask)), (reg))
+
+struct m48t59_private {
+ void __iomem *ioaddr;
+ int irq;
+ struct rtc_device *rtc;
+ spinlock_t lock; /* serialize the NVRAM and RTC access */
+};
+
+/*
+ * This is the generic access method when the chip is memory-mapped
+ */
+static void
+m48t59_mem_writeb(struct device *dev, u32 ofs, u8 val)
+{
+ struct m48t59_private *m48t59 = dev_get_drvdata(dev);
+
+ writeb(val, m48t59->ioaddr+ofs);
+}
+
+static u8
+m48t59_mem_readb(struct device *dev, u32 ofs)
+{
+ struct m48t59_private *m48t59 = dev_get_drvdata(dev);
+
+ return readb(m48t59->ioaddr+ofs);
+}
+
+/*
+ * NOTE: M48T59 only uses BCD mode
+ */
+static int m48t59_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct m48t59_plat_data *pdata = dev_get_platdata(dev);
+ struct m48t59_private *m48t59 = dev_get_drvdata(dev);
+ unsigned long flags;
+ u8 val;
+
+ spin_lock_irqsave(&m48t59->lock, flags);
+ /* Issue the READ command */
+ M48T59_SET_BITS(M48T59_CNTL_READ, M48T59_CNTL);
+
+ tm->tm_year = bcd2bin(M48T59_READ(M48T59_YEAR));
+ /* tm_mon is 0-11 */
+ tm->tm_mon = bcd2bin(M48T59_READ(M48T59_MONTH)) - 1;
+ tm->tm_mday = bcd2bin(M48T59_READ(M48T59_MDAY));
+
+ val = M48T59_READ(M48T59_WDAY);
+ if ((pdata->type == M48T59RTC_TYPE_M48T59) &&
+ (val & M48T59_WDAY_CEB) && (val & M48T59_WDAY_CB)) {
+ dev_dbg(dev, "Century bit is enabled\n");
+ tm->tm_year += 100; /* one century */
+ }
+#ifdef CONFIG_SPARC
+ /* Sun SPARC machines count years since 1968 */
+ tm->tm_year += 68;
+#endif
+
+ tm->tm_wday = bcd2bin(val & 0x07);
+ tm->tm_hour = bcd2bin(M48T59_READ(M48T59_HOUR) & 0x3F);
+ tm->tm_min = bcd2bin(M48T59_READ(M48T59_MIN) & 0x7F);
+ tm->tm_sec = bcd2bin(M48T59_READ(M48T59_SEC) & 0x7F);
+
+ /* Clear the READ bit */
+ M48T59_CLEAR_BITS(M48T59_CNTL_READ, M48T59_CNTL);
+ spin_unlock_irqrestore(&m48t59->lock, flags);
+
+ dev_dbg(dev, "RTC read time %ptR\n", tm);
+ return 0;
+}
+
+static int m48t59_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct m48t59_plat_data *pdata = dev_get_platdata(dev);
+ struct m48t59_private *m48t59 = dev_get_drvdata(dev);
+ unsigned long flags;
+ u8 val = 0;
+ int year = tm->tm_year;
+
+#ifdef CONFIG_SPARC
+ /* Sun SPARC machines count years since 1968 */
+ year -= 68;
+#endif
+
+ dev_dbg(dev, "RTC set time %04d-%02d-%02d %02d/%02d/%02d\n",
+ year + 1900, tm->tm_mon, tm->tm_mday,
+ tm->tm_hour, tm->tm_min, tm->tm_sec);
+
+ if (year < 0)
+ return -EINVAL;
+
+ spin_lock_irqsave(&m48t59->lock, flags);
+ /* Issue the WRITE command */
+ M48T59_SET_BITS(M48T59_CNTL_WRITE, M48T59_CNTL);
+
+ M48T59_WRITE((bin2bcd(tm->tm_sec) & 0x7F), M48T59_SEC);
+ M48T59_WRITE((bin2bcd(tm->tm_min) & 0x7F), M48T59_MIN);
+ M48T59_WRITE((bin2bcd(tm->tm_hour) & 0x3F), M48T59_HOUR);
+ M48T59_WRITE((bin2bcd(tm->tm_mday) & 0x3F), M48T59_MDAY);
+ /* tm_mon is 0-11 */
+ M48T59_WRITE((bin2bcd(tm->tm_mon + 1) & 0x1F), M48T59_MONTH);
+ M48T59_WRITE(bin2bcd(year % 100), M48T59_YEAR);
+
+ if (pdata->type == M48T59RTC_TYPE_M48T59 && (year / 100))
+ val = (M48T59_WDAY_CEB | M48T59_WDAY_CB);
+ val |= (bin2bcd(tm->tm_wday) & 0x07);
+ M48T59_WRITE(val, M48T59_WDAY);
+
+ /* Clear the WRITE bit */
+ M48T59_CLEAR_BITS(M48T59_CNTL_WRITE, M48T59_CNTL);
+ spin_unlock_irqrestore(&m48t59->lock, flags);
+ return 0;
+}
+
+/*
+ * Read alarm time and date in RTC
+ */
+static int m48t59_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct m48t59_plat_data *pdata = dev_get_platdata(dev);
+ struct m48t59_private *m48t59 = dev_get_drvdata(dev);
+ struct rtc_time *tm = &alrm->time;
+ unsigned long flags;
+ u8 val;
+
+ /* If no irq, we don't support ALARM */
+ if (m48t59->irq == NO_IRQ)
+ return -EIO;
+
+ spin_lock_irqsave(&m48t59->lock, flags);
+ /* Issue the READ command */
+ M48T59_SET_BITS(M48T59_CNTL_READ, M48T59_CNTL);
+
+ tm->tm_year = bcd2bin(M48T59_READ(M48T59_YEAR));
+#ifdef CONFIG_SPARC
+ /* Sun SPARC machines count years since 1968 */
+ tm->tm_year += 68;
+#endif
+ /* tm_mon is 0-11 */
+ tm->tm_mon = bcd2bin(M48T59_READ(M48T59_MONTH)) - 1;
+
+ val = M48T59_READ(M48T59_WDAY);
+ if ((val & M48T59_WDAY_CEB) && (val & M48T59_WDAY_CB))
+ tm->tm_year += 100; /* one century */
+
+ tm->tm_mday = bcd2bin(M48T59_READ(M48T59_ALARM_DATE));
+ tm->tm_hour = bcd2bin(M48T59_READ(M48T59_ALARM_HOUR));
+ tm->tm_min = bcd2bin(M48T59_READ(M48T59_ALARM_MIN));
+ tm->tm_sec = bcd2bin(M48T59_READ(M48T59_ALARM_SEC));
+
+ /* Clear the READ bit */
+ M48T59_CLEAR_BITS(M48T59_CNTL_READ, M48T59_CNTL);
+ spin_unlock_irqrestore(&m48t59->lock, flags);
+
+ dev_dbg(dev, "RTC read alarm time %ptR\n", tm);
+ return rtc_valid_tm(tm);
+}
+
+/*
+ * Set alarm time and date in RTC
+ */
+static int m48t59_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct m48t59_plat_data *pdata = dev_get_platdata(dev);
+ struct m48t59_private *m48t59 = dev_get_drvdata(dev);
+ struct rtc_time *tm = &alrm->time;
+ u8 mday, hour, min, sec;
+ unsigned long flags;
+ int year = tm->tm_year;
+
+#ifdef CONFIG_SPARC
+ /* Sun SPARC machines count years since 1968 */
+ year -= 68;
+#endif
+
+ /* If no irq, we don't support ALARM */
+ if (m48t59->irq == NO_IRQ)
+ return -EIO;
+
+ if (year < 0)
+ return -EINVAL;
+
+ /*
+ * 0xff means "always match"
+ */
+ mday = tm->tm_mday;
+ mday = (mday >= 1 && mday <= 31) ? bin2bcd(mday) : 0xff;
+ if (mday == 0xff)
+ mday = M48T59_READ(M48T59_MDAY);
+
+ hour = tm->tm_hour;
+ hour = (hour < 24) ? bin2bcd(hour) : 0x00;
+
+ min = tm->tm_min;
+ min = (min < 60) ? bin2bcd(min) : 0x00;
+
+ sec = tm->tm_sec;
+ sec = (sec < 60) ? bin2bcd(sec) : 0x00;
+
+ spin_lock_irqsave(&m48t59->lock, flags);
+ /* Issue the WRITE command */
+ M48T59_SET_BITS(M48T59_CNTL_WRITE, M48T59_CNTL);
+
+ M48T59_WRITE(mday, M48T59_ALARM_DATE);
+ M48T59_WRITE(hour, M48T59_ALARM_HOUR);
+ M48T59_WRITE(min, M48T59_ALARM_MIN);
+ M48T59_WRITE(sec, M48T59_ALARM_SEC);
+
+ /* Clear the WRITE bit */
+ M48T59_CLEAR_BITS(M48T59_CNTL_WRITE, M48T59_CNTL);
+ spin_unlock_irqrestore(&m48t59->lock, flags);
+
+ dev_dbg(dev, "RTC set alarm time %04d-%02d-%02d %02d/%02d/%02d\n",
+ year + 1900, tm->tm_mon, tm->tm_mday,
+ tm->tm_hour, tm->tm_min, tm->tm_sec);
+ return 0;
+}
+
+/*
+ * Handle commands from user-space
+ */
+static int m48t59_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+ struct m48t59_plat_data *pdata = dev_get_platdata(dev);
+ struct m48t59_private *m48t59 = dev_get_drvdata(dev);
+ unsigned long flags;
+
+ spin_lock_irqsave(&m48t59->lock, flags);
+ if (enabled)
+ M48T59_WRITE(M48T59_INTR_AFE, M48T59_INTR);
+ else
+ M48T59_WRITE(0x00, M48T59_INTR);
+ spin_unlock_irqrestore(&m48t59->lock, flags);
+
+ return 0;
+}
+
+static int m48t59_rtc_proc(struct device *dev, struct seq_file *seq)
+{
+ struct m48t59_plat_data *pdata = dev_get_platdata(dev);
+ struct m48t59_private *m48t59 = dev_get_drvdata(dev);
+ unsigned long flags;
+ u8 val;
+
+ spin_lock_irqsave(&m48t59->lock, flags);
+ val = M48T59_READ(M48T59_FLAGS);
+ spin_unlock_irqrestore(&m48t59->lock, flags);
+
+ seq_printf(seq, "battery\t\t: %s\n",
+ (val & M48T59_FLAGS_BF) ? "low" : "normal");
+ return 0;
+}
+
+/*
+ * IRQ handler for the RTC
+ */
+static irqreturn_t m48t59_rtc_interrupt(int irq, void *dev_id)
+{
+ struct device *dev = (struct device *)dev_id;
+ struct m48t59_plat_data *pdata = dev_get_platdata(dev);
+ struct m48t59_private *m48t59 = dev_get_drvdata(dev);
+ u8 event;
+
+ spin_lock(&m48t59->lock);
+ event = M48T59_READ(M48T59_FLAGS);
+ spin_unlock(&m48t59->lock);
+
+ if (event & M48T59_FLAGS_AF) {
+ rtc_update_irq(m48t59->rtc, 1, (RTC_AF | RTC_IRQF));
+ return IRQ_HANDLED;
+ }
+
+ return IRQ_NONE;
+}
+
+static const struct rtc_class_ops m48t59_rtc_ops = {
+ .read_time = m48t59_rtc_read_time,
+ .set_time = m48t59_rtc_set_time,
+ .read_alarm = m48t59_rtc_readalarm,
+ .set_alarm = m48t59_rtc_setalarm,
+ .proc = m48t59_rtc_proc,
+ .alarm_irq_enable = m48t59_rtc_alarm_irq_enable,
+};
+
+static int m48t59_nvram_read(void *priv, unsigned int offset, void *val,
+ size_t size)
+{
+ struct platform_device *pdev = priv;
+ struct device *dev = &pdev->dev;
+ struct m48t59_plat_data *pdata = dev_get_platdata(&pdev->dev);
+ struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
+ ssize_t cnt = 0;
+ unsigned long flags;
+ u8 *buf = val;
+
+ spin_lock_irqsave(&m48t59->lock, flags);
+
+ for (; cnt < size; cnt++)
+ *buf++ = M48T59_READ(cnt);
+
+ spin_unlock_irqrestore(&m48t59->lock, flags);
+
+ return 0;
+}
+
+static int m48t59_nvram_write(void *priv, unsigned int offset, void *val,
+ size_t size)
+{
+ struct platform_device *pdev = priv;
+ struct device *dev = &pdev->dev;
+ struct m48t59_plat_data *pdata = dev_get_platdata(&pdev->dev);
+ struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
+ ssize_t cnt = 0;
+ unsigned long flags;
+ u8 *buf = val;
+
+ spin_lock_irqsave(&m48t59->lock, flags);
+
+ for (; cnt < size; cnt++)
+ M48T59_WRITE(*buf++, cnt);
+
+ spin_unlock_irqrestore(&m48t59->lock, flags);
+
+ return 0;
+}
+
+static int m48t59_rtc_probe(struct platform_device *pdev)
+{
+ struct m48t59_plat_data *pdata = dev_get_platdata(&pdev->dev);
+ struct m48t59_private *m48t59 = NULL;
+ struct resource *res;
+ int ret = -ENOMEM;
+ struct nvmem_config nvmem_cfg = {
+ .name = "m48t59-",
+ .word_size = 1,
+ .stride = 1,
+ .reg_read = m48t59_nvram_read,
+ .reg_write = m48t59_nvram_write,
+ .priv = pdev,
+ };
+
+ /* This chip could be memory-mapped or I/O-mapped */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+ if (!res)
+ return -EINVAL;
+ }
+
+ if (res->flags & IORESOURCE_IO) {
+ /* If we are I/O-mapped, the platform should provide
+ * the operations accessing chip registers.
+ */
+ if (!pdata || !pdata->write_byte || !pdata->read_byte)
+ return -EINVAL;
+ } else if (res->flags & IORESOURCE_MEM) {
+ /* we are memory-mapped */
+ if (!pdata) {
+ pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata),
+ GFP_KERNEL);
+ if (!pdata)
+ return -ENOMEM;
+ /* Ensure we only kmalloc platform data once */
+ pdev->dev.platform_data = pdata;
+ }
+ if (!pdata->type)
+ pdata->type = M48T59RTC_TYPE_M48T59;
+
+ /* Try to use the generic memory read/write ops */
+ if (!pdata->write_byte)
+ pdata->write_byte = m48t59_mem_writeb;
+ if (!pdata->read_byte)
+ pdata->read_byte = m48t59_mem_readb;
+ }
+
+ m48t59 = devm_kzalloc(&pdev->dev, sizeof(*m48t59), GFP_KERNEL);
+ if (!m48t59)
+ return -ENOMEM;
+
+ m48t59->ioaddr = pdata->ioaddr;
+
+ if (!m48t59->ioaddr) {
+ /* ioaddr not mapped externally */
+ m48t59->ioaddr = devm_ioremap(&pdev->dev, res->start,
+ resource_size(res));
+ if (!m48t59->ioaddr)
+ return ret;
+ }
+
+ /* Try to get irq number. We also can work in
+ * the mode without IRQ.
+ */
+ m48t59->irq = platform_get_irq_optional(pdev, 0);
+ if (m48t59->irq <= 0)
+ m48t59->irq = NO_IRQ;
+
+ if (m48t59->irq != NO_IRQ) {
+ ret = devm_request_irq(&pdev->dev, m48t59->irq,
+ m48t59_rtc_interrupt, IRQF_SHARED,
+ "rtc-m48t59", &pdev->dev);
+ if (ret)
+ return ret;
+ }
+
+ m48t59->rtc = devm_rtc_allocate_device(&pdev->dev);
+ if (IS_ERR(m48t59->rtc))
+ return PTR_ERR(m48t59->rtc);
+
+ switch (pdata->type) {
+ case M48T59RTC_TYPE_M48T59:
+ pdata->offset = 0x1ff0;
+ break;
+ case M48T59RTC_TYPE_M48T02:
+ clear_bit(RTC_FEATURE_ALARM, m48t59->rtc->features);
+ pdata->offset = 0x7f0;
+ break;
+ case M48T59RTC_TYPE_M48T08:
+ clear_bit(RTC_FEATURE_ALARM, m48t59->rtc->features);
+ pdata->offset = 0x1ff0;
+ break;
+ default:
+ dev_err(&pdev->dev, "Unknown RTC type\n");
+ return -ENODEV;
+ }
+
+ spin_lock_init(&m48t59->lock);
+ platform_set_drvdata(pdev, m48t59);
+
+ m48t59->rtc->ops = &m48t59_rtc_ops;
+
+ nvmem_cfg.size = pdata->offset;
+ ret = devm_rtc_nvmem_register(m48t59->rtc, &nvmem_cfg);
+ if (ret)
+ return ret;
+
+ ret = devm_rtc_register_device(m48t59->rtc);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+/* work with hotplug and coldplug */
+MODULE_ALIAS("platform:rtc-m48t59");
+
+static struct platform_driver m48t59_rtc_driver = {
+ .driver = {
+ .name = "rtc-m48t59",
+ },
+ .probe = m48t59_rtc_probe,
+};
+
+module_platform_driver(m48t59_rtc_driver);
+
+MODULE_AUTHOR("Mark Zhan <rongkai.zhan@windriver.com>");
+MODULE_DESCRIPTION("M48T59/M48T02/M48T08 RTC driver");
+MODULE_LICENSE("GPL");