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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/spi/spi-mpc52xx.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/spi/spi-mpc52xx.c')
-rw-r--r--drivers/spi/spi-mpc52xx.c550
1 files changed, 550 insertions, 0 deletions
diff --git a/drivers/spi/spi-mpc52xx.c b/drivers/spi/spi-mpc52xx.c
new file mode 100644
index 000000000..7b64e64c6
--- /dev/null
+++ b/drivers/spi/spi-mpc52xx.c
@@ -0,0 +1,550 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * MPC52xx SPI bus driver.
+ *
+ * Copyright (C) 2008 Secret Lab Technologies Ltd.
+ *
+ * This is the driver for the MPC5200's dedicated SPI controller.
+ *
+ * Note: this driver does not support the MPC5200 PSC in SPI mode. For
+ * that driver see drivers/spi/mpc52xx_psc_spi.c
+ */
+
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/of_platform.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/spi/spi.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#include <asm/time.h>
+#include <asm/mpc52xx.h>
+
+MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
+MODULE_DESCRIPTION("MPC52xx SPI (non-PSC) Driver");
+MODULE_LICENSE("GPL");
+
+/* Register offsets */
+#define SPI_CTRL1 0x00
+#define SPI_CTRL1_SPIE (1 << 7)
+#define SPI_CTRL1_SPE (1 << 6)
+#define SPI_CTRL1_MSTR (1 << 4)
+#define SPI_CTRL1_CPOL (1 << 3)
+#define SPI_CTRL1_CPHA (1 << 2)
+#define SPI_CTRL1_SSOE (1 << 1)
+#define SPI_CTRL1_LSBFE (1 << 0)
+
+#define SPI_CTRL2 0x01
+#define SPI_BRR 0x04
+
+#define SPI_STATUS 0x05
+#define SPI_STATUS_SPIF (1 << 7)
+#define SPI_STATUS_WCOL (1 << 6)
+#define SPI_STATUS_MODF (1 << 4)
+
+#define SPI_DATA 0x09
+#define SPI_PORTDATA 0x0d
+#define SPI_DATADIR 0x10
+
+/* FSM state return values */
+#define FSM_STOP 0 /* Nothing more for the state machine to */
+ /* do. If something interesting happens */
+ /* then an IRQ will be received */
+#define FSM_POLL 1 /* need to poll for completion, an IRQ is */
+ /* not expected */
+#define FSM_CONTINUE 2 /* Keep iterating the state machine */
+
+/* Driver internal data */
+struct mpc52xx_spi {
+ struct spi_master *master;
+ void __iomem *regs;
+ int irq0; /* MODF irq */
+ int irq1; /* SPIF irq */
+ unsigned int ipb_freq;
+
+ /* Statistics; not used now, but will be reintroduced for debugfs */
+ int msg_count;
+ int wcol_count;
+ int wcol_ticks;
+ u32 wcol_tx_timestamp;
+ int modf_count;
+ int byte_count;
+
+ struct list_head queue; /* queue of pending messages */
+ spinlock_t lock;
+ struct work_struct work;
+
+ /* Details of current transfer (length, and buffer pointers) */
+ struct spi_message *message; /* current message */
+ struct spi_transfer *transfer; /* current transfer */
+ int (*state)(int irq, struct mpc52xx_spi *ms, u8 status, u8 data);
+ int len;
+ int timestamp;
+ u8 *rx_buf;
+ const u8 *tx_buf;
+ int cs_change;
+ int gpio_cs_count;
+ struct gpio_desc **gpio_cs;
+};
+
+/*
+ * CS control function
+ */
+static void mpc52xx_spi_chipsel(struct mpc52xx_spi *ms, int value)
+{
+ int cs;
+
+ if (ms->gpio_cs_count > 0) {
+ cs = ms->message->spi->chip_select;
+ gpiod_set_value(ms->gpio_cs[cs], value);
+ } else {
+ out_8(ms->regs + SPI_PORTDATA, value ? 0 : 0x08);
+ }
+}
+
+/*
+ * Start a new transfer. This is called both by the idle state
+ * for the first transfer in a message, and by the wait state when the
+ * previous transfer in a message is complete.
+ */
+static void mpc52xx_spi_start_transfer(struct mpc52xx_spi *ms)
+{
+ ms->rx_buf = ms->transfer->rx_buf;
+ ms->tx_buf = ms->transfer->tx_buf;
+ ms->len = ms->transfer->len;
+
+ /* Activate the chip select */
+ if (ms->cs_change)
+ mpc52xx_spi_chipsel(ms, 1);
+ ms->cs_change = ms->transfer->cs_change;
+
+ /* Write out the first byte */
+ ms->wcol_tx_timestamp = mftb();
+ if (ms->tx_buf)
+ out_8(ms->regs + SPI_DATA, *ms->tx_buf++);
+ else
+ out_8(ms->regs + SPI_DATA, 0);
+}
+
+/* Forward declaration of state handlers */
+static int mpc52xx_spi_fsmstate_transfer(int irq, struct mpc52xx_spi *ms,
+ u8 status, u8 data);
+static int mpc52xx_spi_fsmstate_wait(int irq, struct mpc52xx_spi *ms,
+ u8 status, u8 data);
+
+/*
+ * IDLE state
+ *
+ * No transfers are in progress; if another transfer is pending then retrieve
+ * it and kick it off. Otherwise, stop processing the state machine
+ */
+static int
+mpc52xx_spi_fsmstate_idle(int irq, struct mpc52xx_spi *ms, u8 status, u8 data)
+{
+ struct spi_device *spi;
+ int spr, sppr;
+ u8 ctrl1;
+
+ if (status && irq)
+ dev_err(&ms->master->dev, "spurious irq, status=0x%.2x\n",
+ status);
+
+ /* Check if there is another transfer waiting. */
+ if (list_empty(&ms->queue))
+ return FSM_STOP;
+
+ /* get the head of the queue */
+ ms->message = list_first_entry(&ms->queue, struct spi_message, queue);
+ list_del_init(&ms->message->queue);
+
+ /* Setup the controller parameters */
+ ctrl1 = SPI_CTRL1_SPIE | SPI_CTRL1_SPE | SPI_CTRL1_MSTR;
+ spi = ms->message->spi;
+ if (spi->mode & SPI_CPHA)
+ ctrl1 |= SPI_CTRL1_CPHA;
+ if (spi->mode & SPI_CPOL)
+ ctrl1 |= SPI_CTRL1_CPOL;
+ if (spi->mode & SPI_LSB_FIRST)
+ ctrl1 |= SPI_CTRL1_LSBFE;
+ out_8(ms->regs + SPI_CTRL1, ctrl1);
+
+ /* Setup the controller speed */
+ /* minimum divider is '2'. Also, add '1' to force rounding the
+ * divider up. */
+ sppr = ((ms->ipb_freq / ms->message->spi->max_speed_hz) + 1) >> 1;
+ spr = 0;
+ if (sppr < 1)
+ sppr = 1;
+ while (((sppr - 1) & ~0x7) != 0) {
+ sppr = (sppr + 1) >> 1; /* add '1' to force rounding up */
+ spr++;
+ }
+ sppr--; /* sppr quantity in register is offset by 1 */
+ if (spr > 7) {
+ /* Don't overrun limits of SPI baudrate register */
+ spr = 7;
+ sppr = 7;
+ }
+ out_8(ms->regs + SPI_BRR, sppr << 4 | spr); /* Set speed */
+
+ ms->cs_change = 1;
+ ms->transfer = container_of(ms->message->transfers.next,
+ struct spi_transfer, transfer_list);
+
+ mpc52xx_spi_start_transfer(ms);
+ ms->state = mpc52xx_spi_fsmstate_transfer;
+
+ return FSM_CONTINUE;
+}
+
+/*
+ * TRANSFER state
+ *
+ * In the middle of a transfer. If the SPI core has completed processing
+ * a byte, then read out the received data and write out the next byte
+ * (unless this transfer is finished; in which case go on to the wait
+ * state)
+ */
+static int mpc52xx_spi_fsmstate_transfer(int irq, struct mpc52xx_spi *ms,
+ u8 status, u8 data)
+{
+ if (!status)
+ return ms->irq0 ? FSM_STOP : FSM_POLL;
+
+ if (status & SPI_STATUS_WCOL) {
+ /* The SPI controller is stoopid. At slower speeds, it may
+ * raise the SPIF flag before the state machine is actually
+ * finished, which causes a collision (internal to the state
+ * machine only). The manual recommends inserting a delay
+ * between receiving the interrupt and sending the next byte,
+ * but it can also be worked around simply by retrying the
+ * transfer which is what we do here. */
+ ms->wcol_count++;
+ ms->wcol_ticks += mftb() - ms->wcol_tx_timestamp;
+ ms->wcol_tx_timestamp = mftb();
+ data = 0;
+ if (ms->tx_buf)
+ data = *(ms->tx_buf - 1);
+ out_8(ms->regs + SPI_DATA, data); /* try again */
+ return FSM_CONTINUE;
+ } else if (status & SPI_STATUS_MODF) {
+ ms->modf_count++;
+ dev_err(&ms->master->dev, "mode fault\n");
+ mpc52xx_spi_chipsel(ms, 0);
+ ms->message->status = -EIO;
+ if (ms->message->complete)
+ ms->message->complete(ms->message->context);
+ ms->state = mpc52xx_spi_fsmstate_idle;
+ return FSM_CONTINUE;
+ }
+
+ /* Read data out of the spi device */
+ ms->byte_count++;
+ if (ms->rx_buf)
+ *ms->rx_buf++ = data;
+
+ /* Is the transfer complete? */
+ ms->len--;
+ if (ms->len == 0) {
+ ms->timestamp = mftb();
+ if (ms->transfer->delay.unit == SPI_DELAY_UNIT_USECS)
+ ms->timestamp += ms->transfer->delay.value *
+ tb_ticks_per_usec;
+ ms->state = mpc52xx_spi_fsmstate_wait;
+ return FSM_CONTINUE;
+ }
+
+ /* Write out the next byte */
+ ms->wcol_tx_timestamp = mftb();
+ if (ms->tx_buf)
+ out_8(ms->regs + SPI_DATA, *ms->tx_buf++);
+ else
+ out_8(ms->regs + SPI_DATA, 0);
+
+ return FSM_CONTINUE;
+}
+
+/*
+ * WAIT state
+ *
+ * A transfer has completed; need to wait for the delay period to complete
+ * before starting the next transfer
+ */
+static int
+mpc52xx_spi_fsmstate_wait(int irq, struct mpc52xx_spi *ms, u8 status, u8 data)
+{
+ if (status && irq)
+ dev_err(&ms->master->dev, "spurious irq, status=0x%.2x\n",
+ status);
+
+ if (((int)mftb()) - ms->timestamp < 0)
+ return FSM_POLL;
+
+ ms->message->actual_length += ms->transfer->len;
+
+ /* Check if there is another transfer in this message. If there
+ * aren't then deactivate CS, notify sender, and drop back to idle
+ * to start the next message. */
+ if (ms->transfer->transfer_list.next == &ms->message->transfers) {
+ ms->msg_count++;
+ mpc52xx_spi_chipsel(ms, 0);
+ ms->message->status = 0;
+ if (ms->message->complete)
+ ms->message->complete(ms->message->context);
+ ms->state = mpc52xx_spi_fsmstate_idle;
+ return FSM_CONTINUE;
+ }
+
+ /* There is another transfer; kick it off */
+
+ if (ms->cs_change)
+ mpc52xx_spi_chipsel(ms, 0);
+
+ ms->transfer = container_of(ms->transfer->transfer_list.next,
+ struct spi_transfer, transfer_list);
+ mpc52xx_spi_start_transfer(ms);
+ ms->state = mpc52xx_spi_fsmstate_transfer;
+ return FSM_CONTINUE;
+}
+
+/**
+ * mpc52xx_spi_fsm_process - Finite State Machine iteration function
+ * @irq: irq number that triggered the FSM or 0 for polling
+ * @ms: pointer to mpc52xx_spi driver data
+ */
+static void mpc52xx_spi_fsm_process(int irq, struct mpc52xx_spi *ms)
+{
+ int rc = FSM_CONTINUE;
+ u8 status, data;
+
+ while (rc == FSM_CONTINUE) {
+ /* Interrupt cleared by read of STATUS followed by
+ * read of DATA registers */
+ status = in_8(ms->regs + SPI_STATUS);
+ data = in_8(ms->regs + SPI_DATA);
+ rc = ms->state(irq, ms, status, data);
+ }
+
+ if (rc == FSM_POLL)
+ schedule_work(&ms->work);
+}
+
+/**
+ * mpc52xx_spi_irq - IRQ handler
+ */
+static irqreturn_t mpc52xx_spi_irq(int irq, void *_ms)
+{
+ struct mpc52xx_spi *ms = _ms;
+ spin_lock(&ms->lock);
+ mpc52xx_spi_fsm_process(irq, ms);
+ spin_unlock(&ms->lock);
+ return IRQ_HANDLED;
+}
+
+/**
+ * mpc52xx_spi_wq - Workqueue function for polling the state machine
+ */
+static void mpc52xx_spi_wq(struct work_struct *work)
+{
+ struct mpc52xx_spi *ms = container_of(work, struct mpc52xx_spi, work);
+ unsigned long flags;
+
+ spin_lock_irqsave(&ms->lock, flags);
+ mpc52xx_spi_fsm_process(0, ms);
+ spin_unlock_irqrestore(&ms->lock, flags);
+}
+
+/*
+ * spi_master ops
+ */
+
+static int mpc52xx_spi_transfer(struct spi_device *spi, struct spi_message *m)
+{
+ struct mpc52xx_spi *ms = spi_master_get_devdata(spi->master);
+ unsigned long flags;
+
+ m->actual_length = 0;
+ m->status = -EINPROGRESS;
+
+ spin_lock_irqsave(&ms->lock, flags);
+ list_add_tail(&m->queue, &ms->queue);
+ spin_unlock_irqrestore(&ms->lock, flags);
+ schedule_work(&ms->work);
+
+ return 0;
+}
+
+/*
+ * OF Platform Bus Binding
+ */
+static int mpc52xx_spi_probe(struct platform_device *op)
+{
+ struct spi_master *master;
+ struct mpc52xx_spi *ms;
+ struct gpio_desc *gpio_cs;
+ void __iomem *regs;
+ u8 ctrl1;
+ int rc, i = 0;
+
+ /* MMIO registers */
+ dev_dbg(&op->dev, "probing mpc5200 SPI device\n");
+ regs = of_iomap(op->dev.of_node, 0);
+ if (!regs)
+ return -ENODEV;
+
+ /* initialize the device */
+ ctrl1 = SPI_CTRL1_SPIE | SPI_CTRL1_SPE | SPI_CTRL1_MSTR;
+ out_8(regs + SPI_CTRL1, ctrl1);
+ out_8(regs + SPI_CTRL2, 0x0);
+ out_8(regs + SPI_DATADIR, 0xe); /* Set output pins */
+ out_8(regs + SPI_PORTDATA, 0x8); /* Deassert /SS signal */
+
+ /* Clear the status register and re-read it to check for a MODF
+ * failure. This driver cannot currently handle multiple masters
+ * on the SPI bus. This fault will also occur if the SPI signals
+ * are not connected to any pins (port_config setting) */
+ in_8(regs + SPI_STATUS);
+ out_8(regs + SPI_CTRL1, ctrl1);
+
+ in_8(regs + SPI_DATA);
+ if (in_8(regs + SPI_STATUS) & SPI_STATUS_MODF) {
+ dev_err(&op->dev, "mode fault; is port_config correct?\n");
+ rc = -EIO;
+ goto err_init;
+ }
+
+ dev_dbg(&op->dev, "allocating spi_master struct\n");
+ master = spi_alloc_master(&op->dev, sizeof(*ms));
+ if (!master) {
+ rc = -ENOMEM;
+ goto err_alloc;
+ }
+
+ master->transfer = mpc52xx_spi_transfer;
+ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
+ master->bits_per_word_mask = SPI_BPW_MASK(8);
+ master->dev.of_node = op->dev.of_node;
+
+ platform_set_drvdata(op, master);
+
+ ms = spi_master_get_devdata(master);
+ ms->master = master;
+ ms->regs = regs;
+ ms->irq0 = irq_of_parse_and_map(op->dev.of_node, 0);
+ ms->irq1 = irq_of_parse_and_map(op->dev.of_node, 1);
+ ms->state = mpc52xx_spi_fsmstate_idle;
+ ms->ipb_freq = mpc5xxx_get_bus_frequency(&op->dev);
+ ms->gpio_cs_count = gpiod_count(&op->dev, NULL);
+ if (ms->gpio_cs_count > 0) {
+ master->num_chipselect = ms->gpio_cs_count;
+ ms->gpio_cs = kmalloc_array(ms->gpio_cs_count,
+ sizeof(*ms->gpio_cs),
+ GFP_KERNEL);
+ if (!ms->gpio_cs) {
+ rc = -ENOMEM;
+ goto err_alloc_gpio;
+ }
+
+ for (i = 0; i < ms->gpio_cs_count; i++) {
+ gpio_cs = gpiod_get_index(&op->dev,
+ NULL, i, GPIOD_OUT_LOW);
+ rc = PTR_ERR_OR_ZERO(gpio_cs);
+ if (rc) {
+ dev_err(&op->dev,
+ "failed to get spi cs gpio #%d: %d\n",
+ i, rc);
+ goto err_gpio;
+ }
+
+ ms->gpio_cs[i] = gpio_cs;
+ }
+ }
+
+ spin_lock_init(&ms->lock);
+ INIT_LIST_HEAD(&ms->queue);
+ INIT_WORK(&ms->work, mpc52xx_spi_wq);
+
+ /* Decide if interrupts can be used */
+ if (ms->irq0 && ms->irq1) {
+ rc = request_irq(ms->irq0, mpc52xx_spi_irq, 0,
+ "mpc5200-spi-modf", ms);
+ rc |= request_irq(ms->irq1, mpc52xx_spi_irq, 0,
+ "mpc5200-spi-spif", ms);
+ if (rc) {
+ free_irq(ms->irq0, ms);
+ free_irq(ms->irq1, ms);
+ ms->irq0 = ms->irq1 = 0;
+ }
+ } else {
+ /* operate in polled mode */
+ ms->irq0 = ms->irq1 = 0;
+ }
+
+ if (!ms->irq0)
+ dev_info(&op->dev, "using polled mode\n");
+
+ dev_dbg(&op->dev, "registering spi_master struct\n");
+ rc = spi_register_master(master);
+ if (rc)
+ goto err_register;
+
+ dev_info(&ms->master->dev, "registered MPC5200 SPI bus\n");
+
+ return rc;
+
+ err_register:
+ dev_err(&ms->master->dev, "initialization failed\n");
+ err_gpio:
+ while (i-- > 0)
+ gpiod_put(ms->gpio_cs[i]);
+
+ kfree(ms->gpio_cs);
+ err_alloc_gpio:
+ spi_master_put(master);
+ err_alloc:
+ err_init:
+ iounmap(regs);
+ return rc;
+}
+
+static int mpc52xx_spi_remove(struct platform_device *op)
+{
+ struct spi_master *master = spi_master_get(platform_get_drvdata(op));
+ struct mpc52xx_spi *ms = spi_master_get_devdata(master);
+ int i;
+
+ free_irq(ms->irq0, ms);
+ free_irq(ms->irq1, ms);
+
+ for (i = 0; i < ms->gpio_cs_count; i++)
+ gpiod_put(ms->gpio_cs[i]);
+
+ kfree(ms->gpio_cs);
+ spi_unregister_master(master);
+ iounmap(ms->regs);
+ spi_master_put(master);
+
+ return 0;
+}
+
+static const struct of_device_id mpc52xx_spi_match[] = {
+ { .compatible = "fsl,mpc5200-spi", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, mpc52xx_spi_match);
+
+static struct platform_driver mpc52xx_spi_of_driver = {
+ .driver = {
+ .name = "mpc52xx-spi",
+ .of_match_table = mpc52xx_spi_match,
+ },
+ .probe = mpc52xx_spi_probe,
+ .remove = mpc52xx_spi_remove,
+};
+module_platform_driver(mpc52xx_spi_of_driver);