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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/gpio/gpio-mmio.c | |
download | linux-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 'drivers/gpio/gpio-mmio.c')
-rw-r--r-- | drivers/gpio/gpio-mmio.c | 822 |
1 files changed, 822 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-mmio.c b/drivers/gpio/gpio-mmio.c new file mode 100644 index 000000000..d9dff3dc9 --- /dev/null +++ b/drivers/gpio/gpio-mmio.c @@ -0,0 +1,822 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Generic driver for memory-mapped GPIO controllers. + * + * Copyright 2008 MontaVista Software, Inc. + * Copyright 2008,2010 Anton Vorontsov <cbouatmailru@gmail.com> + * + * ....``.```~~~~````.`.`.`.`.```````'',,,.........`````......`....... + * ...`` ```````.. + * ..The simplest form of a GPIO controller that the driver supports is`` + * `.just a single "data" register, where GPIO state can be read and/or ` + * `,..written. ,,..``~~~~ .....``.`.`.~~.```.`.........``````.``````` + * ````````` + ___ +_/~~|___/~| . ```~~~~~~ ___/___\___ ,~.`.`.`.`````.~~...,,,,... +__________|~$@~~~ %~ /o*o*o*o*o*o\ .. Implementing such a GPIO . +o ` ~~~~\___/~~~~ ` controller in FPGA is ,.` + `....trivial..'~`.```.``` + * ``````` + * .```````~~~~`..`.``.``. + * . The driver supports `... ,..```.`~~~```````````````....````.``,, + * . big-endian notation, just`. .. A bit more sophisticated controllers , + * . register the device with -be`. .with a pair of set/clear-bit registers , + * `.. suffix. ```~~`````....`.` . affecting the data register and the .` + * ``.`.``...``` ```.. output pins are also supported.` + * ^^ `````.`````````.,``~``~``~~`````` + * . ^^ + * ,..`.`.`...````````````......`.`.`.`.`.`..`.`.`.. + * .. The expectation is that in at least some cases . ,-~~~-, + * .this will be used with roll-your-own ASIC/FPGA .` \ / + * .logic in Verilog or VHDL. ~~~`````````..`````~~` \ / + * ..````````......``````````` \o_ + * | + * ^^ / \ + * + * ...`````~~`.....``.`..........``````.`.``.```........``. + * ` 8, 16, 32 and 64 bits registers are supported, and``. + * . the number of GPIOs is determined by the width of ~ + * .. the registers. ,............```.`.`..`.`.~~~.`.`.`~ + * `.......````.``` + */ + +#include <linux/init.h> +#include <linux/err.h> +#include <linux/bug.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/spinlock.h> +#include <linux/compiler.h> +#include <linux/types.h> +#include <linux/errno.h> +#include <linux/log2.h> +#include <linux/ioport.h> +#include <linux/io.h> +#include <linux/gpio/driver.h> +#include <linux/slab.h> +#include <linux/bitops.h> +#include <linux/platform_device.h> +#include <linux/mod_devicetable.h> +#include <linux/of.h> +#include <linux/of_device.h> + +static void bgpio_write8(void __iomem *reg, unsigned long data) +{ + writeb(data, reg); +} + +static unsigned long bgpio_read8(void __iomem *reg) +{ + return readb(reg); +} + +static void bgpio_write16(void __iomem *reg, unsigned long data) +{ + writew(data, reg); +} + +static unsigned long bgpio_read16(void __iomem *reg) +{ + return readw(reg); +} + +static void bgpio_write32(void __iomem *reg, unsigned long data) +{ + writel(data, reg); +} + +static unsigned long bgpio_read32(void __iomem *reg) +{ + return readl(reg); +} + +#if BITS_PER_LONG >= 64 +static void bgpio_write64(void __iomem *reg, unsigned long data) +{ + writeq(data, reg); +} + +static unsigned long bgpio_read64(void __iomem *reg) +{ + return readq(reg); +} +#endif /* BITS_PER_LONG >= 64 */ + +static void bgpio_write16be(void __iomem *reg, unsigned long data) +{ + iowrite16be(data, reg); +} + +static unsigned long bgpio_read16be(void __iomem *reg) +{ + return ioread16be(reg); +} + +static void bgpio_write32be(void __iomem *reg, unsigned long data) +{ + iowrite32be(data, reg); +} + +static unsigned long bgpio_read32be(void __iomem *reg) +{ + return ioread32be(reg); +} + +static unsigned long bgpio_line2mask(struct gpio_chip *gc, unsigned int line) +{ + if (gc->be_bits) + return BIT(gc->bgpio_bits - 1 - line); + return BIT(line); +} + +static int bgpio_get_set(struct gpio_chip *gc, unsigned int gpio) +{ + unsigned long pinmask = bgpio_line2mask(gc, gpio); + bool dir = !!(gc->bgpio_dir & pinmask); + + if (dir) + return !!(gc->read_reg(gc->reg_set) & pinmask); + else + return !!(gc->read_reg(gc->reg_dat) & pinmask); +} + +/* + * This assumes that the bits in the GPIO register are in native endianness. + * We only assign the function pointer if we have that. + */ +static int bgpio_get_set_multiple(struct gpio_chip *gc, unsigned long *mask, + unsigned long *bits) +{ + unsigned long get_mask = 0; + unsigned long set_mask = 0; + + /* Make sure we first clear any bits that are zero when we read the register */ + *bits &= ~*mask; + + set_mask = *mask & gc->bgpio_dir; + get_mask = *mask & ~gc->bgpio_dir; + + if (set_mask) + *bits |= gc->read_reg(gc->reg_set) & set_mask; + if (get_mask) + *bits |= gc->read_reg(gc->reg_dat) & get_mask; + + return 0; +} + +static int bgpio_get(struct gpio_chip *gc, unsigned int gpio) +{ + return !!(gc->read_reg(gc->reg_dat) & bgpio_line2mask(gc, gpio)); +} + +/* + * This only works if the bits in the GPIO register are in native endianness. + */ +static int bgpio_get_multiple(struct gpio_chip *gc, unsigned long *mask, + unsigned long *bits) +{ + /* Make sure we first clear any bits that are zero when we read the register */ + *bits &= ~*mask; + *bits |= gc->read_reg(gc->reg_dat) & *mask; + return 0; +} + +/* + * With big endian mirrored bit order it becomes more tedious. + */ +static int bgpio_get_multiple_be(struct gpio_chip *gc, unsigned long *mask, + unsigned long *bits) +{ + unsigned long readmask = 0; + unsigned long val; + int bit; + + /* Make sure we first clear any bits that are zero when we read the register */ + *bits &= ~*mask; + + /* Create a mirrored mask */ + for_each_set_bit(bit, mask, gc->ngpio) + readmask |= bgpio_line2mask(gc, bit); + + /* Read the register */ + val = gc->read_reg(gc->reg_dat) & readmask; + + /* + * Mirror the result into the "bits" result, this will give line 0 + * in bit 0 ... line 31 in bit 31 for a 32bit register. + */ + for_each_set_bit(bit, &val, gc->ngpio) + *bits |= bgpio_line2mask(gc, bit); + + return 0; +} + +static void bgpio_set_none(struct gpio_chip *gc, unsigned int gpio, int val) +{ +} + +static void bgpio_set(struct gpio_chip *gc, unsigned int gpio, int val) +{ + unsigned long mask = bgpio_line2mask(gc, gpio); + unsigned long flags; + + raw_spin_lock_irqsave(&gc->bgpio_lock, flags); + + if (val) + gc->bgpio_data |= mask; + else + gc->bgpio_data &= ~mask; + + gc->write_reg(gc->reg_dat, gc->bgpio_data); + + raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags); +} + +static void bgpio_set_with_clear(struct gpio_chip *gc, unsigned int gpio, + int val) +{ + unsigned long mask = bgpio_line2mask(gc, gpio); + + if (val) + gc->write_reg(gc->reg_set, mask); + else + gc->write_reg(gc->reg_clr, mask); +} + +static void bgpio_set_set(struct gpio_chip *gc, unsigned int gpio, int val) +{ + unsigned long mask = bgpio_line2mask(gc, gpio); + unsigned long flags; + + raw_spin_lock_irqsave(&gc->bgpio_lock, flags); + + if (val) + gc->bgpio_data |= mask; + else + gc->bgpio_data &= ~mask; + + gc->write_reg(gc->reg_set, gc->bgpio_data); + + raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags); +} + +static void bgpio_multiple_get_masks(struct gpio_chip *gc, + unsigned long *mask, unsigned long *bits, + unsigned long *set_mask, + unsigned long *clear_mask) +{ + int i; + + *set_mask = 0; + *clear_mask = 0; + + for_each_set_bit(i, mask, gc->bgpio_bits) { + if (test_bit(i, bits)) + *set_mask |= bgpio_line2mask(gc, i); + else + *clear_mask |= bgpio_line2mask(gc, i); + } +} + +static void bgpio_set_multiple_single_reg(struct gpio_chip *gc, + unsigned long *mask, + unsigned long *bits, + void __iomem *reg) +{ + unsigned long flags; + unsigned long set_mask, clear_mask; + + raw_spin_lock_irqsave(&gc->bgpio_lock, flags); + + bgpio_multiple_get_masks(gc, mask, bits, &set_mask, &clear_mask); + + gc->bgpio_data |= set_mask; + gc->bgpio_data &= ~clear_mask; + + gc->write_reg(reg, gc->bgpio_data); + + raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags); +} + +static void bgpio_set_multiple(struct gpio_chip *gc, unsigned long *mask, + unsigned long *bits) +{ + bgpio_set_multiple_single_reg(gc, mask, bits, gc->reg_dat); +} + +static void bgpio_set_multiple_set(struct gpio_chip *gc, unsigned long *mask, + unsigned long *bits) +{ + bgpio_set_multiple_single_reg(gc, mask, bits, gc->reg_set); +} + +static void bgpio_set_multiple_with_clear(struct gpio_chip *gc, + unsigned long *mask, + unsigned long *bits) +{ + unsigned long set_mask, clear_mask; + + bgpio_multiple_get_masks(gc, mask, bits, &set_mask, &clear_mask); + + if (set_mask) + gc->write_reg(gc->reg_set, set_mask); + if (clear_mask) + gc->write_reg(gc->reg_clr, clear_mask); +} + +static int bgpio_simple_dir_in(struct gpio_chip *gc, unsigned int gpio) +{ + return 0; +} + +static int bgpio_dir_out_err(struct gpio_chip *gc, unsigned int gpio, + int val) +{ + return -EINVAL; +} + +static int bgpio_simple_dir_out(struct gpio_chip *gc, unsigned int gpio, + int val) +{ + gc->set(gc, gpio, val); + + return 0; +} + +static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&gc->bgpio_lock, flags); + + gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio); + + if (gc->reg_dir_in) + gc->write_reg(gc->reg_dir_in, ~gc->bgpio_dir); + if (gc->reg_dir_out) + gc->write_reg(gc->reg_dir_out, gc->bgpio_dir); + + raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags); + + return 0; +} + +static int bgpio_get_dir(struct gpio_chip *gc, unsigned int gpio) +{ + /* Return 0 if output, 1 if input */ + if (gc->bgpio_dir_unreadable) { + if (gc->bgpio_dir & bgpio_line2mask(gc, gpio)) + return GPIO_LINE_DIRECTION_OUT; + return GPIO_LINE_DIRECTION_IN; + } + + if (gc->reg_dir_out) { + if (gc->read_reg(gc->reg_dir_out) & bgpio_line2mask(gc, gpio)) + return GPIO_LINE_DIRECTION_OUT; + return GPIO_LINE_DIRECTION_IN; + } + + if (gc->reg_dir_in) + if (!(gc->read_reg(gc->reg_dir_in) & bgpio_line2mask(gc, gpio))) + return GPIO_LINE_DIRECTION_OUT; + + return GPIO_LINE_DIRECTION_IN; +} + +static void bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&gc->bgpio_lock, flags); + + gc->bgpio_dir |= bgpio_line2mask(gc, gpio); + + if (gc->reg_dir_in) + gc->write_reg(gc->reg_dir_in, ~gc->bgpio_dir); + if (gc->reg_dir_out) + gc->write_reg(gc->reg_dir_out, gc->bgpio_dir); + + raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags); +} + +static int bgpio_dir_out_dir_first(struct gpio_chip *gc, unsigned int gpio, + int val) +{ + bgpio_dir_out(gc, gpio, val); + gc->set(gc, gpio, val); + return 0; +} + +static int bgpio_dir_out_val_first(struct gpio_chip *gc, unsigned int gpio, + int val) +{ + gc->set(gc, gpio, val); + bgpio_dir_out(gc, gpio, val); + return 0; +} + +static int bgpio_setup_accessors(struct device *dev, + struct gpio_chip *gc, + bool byte_be) +{ + + switch (gc->bgpio_bits) { + case 8: + gc->read_reg = bgpio_read8; + gc->write_reg = bgpio_write8; + break; + case 16: + if (byte_be) { + gc->read_reg = bgpio_read16be; + gc->write_reg = bgpio_write16be; + } else { + gc->read_reg = bgpio_read16; + gc->write_reg = bgpio_write16; + } + break; + case 32: + if (byte_be) { + gc->read_reg = bgpio_read32be; + gc->write_reg = bgpio_write32be; + } else { + gc->read_reg = bgpio_read32; + gc->write_reg = bgpio_write32; + } + break; +#if BITS_PER_LONG >= 64 + case 64: + if (byte_be) { + dev_err(dev, + "64 bit big endian byte order unsupported\n"); + return -EINVAL; + } else { + gc->read_reg = bgpio_read64; + gc->write_reg = bgpio_write64; + } + break; +#endif /* BITS_PER_LONG >= 64 */ + default: + dev_err(dev, "unsupported data width %u bits\n", gc->bgpio_bits); + return -EINVAL; + } + + return 0; +} + +/* + * Create the device and allocate the resources. For setting GPIO's there are + * three supported configurations: + * + * - single input/output register resource (named "dat"). + * - set/clear pair (named "set" and "clr"). + * - single output register resource and single input resource ("set" and + * dat"). + * + * For the single output register, this drives a 1 by setting a bit and a zero + * by clearing a bit. For the set clr pair, this drives a 1 by setting a bit + * in the set register and clears it by setting a bit in the clear register. + * The configuration is detected by which resources are present. + * + * For setting the GPIO direction, there are three supported configurations: + * + * - simple bidirection GPIO that requires no configuration. + * - an output direction register (named "dirout") where a 1 bit + * indicates the GPIO is an output. + * - an input direction register (named "dirin") where a 1 bit indicates + * the GPIO is an input. + */ +static int bgpio_setup_io(struct gpio_chip *gc, + void __iomem *dat, + void __iomem *set, + void __iomem *clr, + unsigned long flags) +{ + + gc->reg_dat = dat; + if (!gc->reg_dat) + return -EINVAL; + + if (set && clr) { + gc->reg_set = set; + gc->reg_clr = clr; + gc->set = bgpio_set_with_clear; + gc->set_multiple = bgpio_set_multiple_with_clear; + } else if (set && !clr) { + gc->reg_set = set; + gc->set = bgpio_set_set; + gc->set_multiple = bgpio_set_multiple_set; + } else if (flags & BGPIOF_NO_OUTPUT) { + gc->set = bgpio_set_none; + gc->set_multiple = NULL; + } else { + gc->set = bgpio_set; + gc->set_multiple = bgpio_set_multiple; + } + + if (!(flags & BGPIOF_UNREADABLE_REG_SET) && + (flags & BGPIOF_READ_OUTPUT_REG_SET)) { + gc->get = bgpio_get_set; + if (!gc->be_bits) + gc->get_multiple = bgpio_get_set_multiple; + /* + * We deliberately avoid assigning the ->get_multiple() call + * for big endian mirrored registers which are ALSO reflecting + * their value in the set register when used as output. It is + * simply too much complexity, let the GPIO core fall back to + * reading each line individually in that fringe case. + */ + } else { + gc->get = bgpio_get; + if (gc->be_bits) + gc->get_multiple = bgpio_get_multiple_be; + else + gc->get_multiple = bgpio_get_multiple; + } + + return 0; +} + +static int bgpio_setup_direction(struct gpio_chip *gc, + void __iomem *dirout, + void __iomem *dirin, + unsigned long flags) +{ + if (dirout || dirin) { + gc->reg_dir_out = dirout; + gc->reg_dir_in = dirin; + if (flags & BGPIOF_NO_SET_ON_INPUT) + gc->direction_output = bgpio_dir_out_dir_first; + else + gc->direction_output = bgpio_dir_out_val_first; + gc->direction_input = bgpio_dir_in; + gc->get_direction = bgpio_get_dir; + } else { + if (flags & BGPIOF_NO_OUTPUT) + gc->direction_output = bgpio_dir_out_err; + else + gc->direction_output = bgpio_simple_dir_out; + gc->direction_input = bgpio_simple_dir_in; + } + + return 0; +} + +static int bgpio_request(struct gpio_chip *chip, unsigned gpio_pin) +{ + if (gpio_pin < chip->ngpio) + return 0; + + return -EINVAL; +} + +/** + * bgpio_init() - Initialize generic GPIO accessor functions + * @gc: the GPIO chip to set up + * @dev: the parent device of the new GPIO chip (compulsory) + * @sz: the size (width) of the MMIO registers in bytes, typically 1, 2 or 4 + * @dat: MMIO address for the register to READ the value of the GPIO lines, it + * is expected that a 1 in the corresponding bit in this register means the + * line is asserted + * @set: MMIO address for the register to SET the value of the GPIO lines, it is + * expected that we write the line with 1 in this register to drive the GPIO line + * high. + * @clr: MMIO address for the register to CLEAR the value of the GPIO lines, it is + * expected that we write the line with 1 in this register to drive the GPIO line + * low. It is allowed to leave this address as NULL, in that case the SET register + * will be assumed to also clear the GPIO lines, by actively writing the line + * with 0. + * @dirout: MMIO address for the register to set the line as OUTPUT. It is assumed + * that setting a line to 1 in this register will turn that line into an + * output line. Conversely, setting the line to 0 will turn that line into + * an input. + * @dirin: MMIO address for the register to set this line as INPUT. It is assumed + * that setting a line to 1 in this register will turn that line into an + * input line. Conversely, setting the line to 0 will turn that line into + * an output. + * @flags: Different flags that will affect the behaviour of the device, such as + * endianness etc. + */ +int bgpio_init(struct gpio_chip *gc, struct device *dev, + unsigned long sz, void __iomem *dat, void __iomem *set, + void __iomem *clr, void __iomem *dirout, void __iomem *dirin, + unsigned long flags) +{ + int ret; + + if (!is_power_of_2(sz)) + return -EINVAL; + + gc->bgpio_bits = sz * 8; + if (gc->bgpio_bits > BITS_PER_LONG) + return -EINVAL; + + raw_spin_lock_init(&gc->bgpio_lock); + gc->parent = dev; + gc->label = dev_name(dev); + gc->base = -1; + gc->ngpio = gc->bgpio_bits; + gc->request = bgpio_request; + gc->be_bits = !!(flags & BGPIOF_BIG_ENDIAN); + + ret = bgpio_setup_io(gc, dat, set, clr, flags); + if (ret) + return ret; + + ret = bgpio_setup_accessors(dev, gc, flags & BGPIOF_BIG_ENDIAN_BYTE_ORDER); + if (ret) + return ret; + + ret = bgpio_setup_direction(gc, dirout, dirin, flags); + if (ret) + return ret; + + gc->bgpio_data = gc->read_reg(gc->reg_dat); + if (gc->set == bgpio_set_set && + !(flags & BGPIOF_UNREADABLE_REG_SET)) + gc->bgpio_data = gc->read_reg(gc->reg_set); + + if (flags & BGPIOF_UNREADABLE_REG_DIR) + gc->bgpio_dir_unreadable = true; + + /* + * Inspect hardware to find initial direction setting. + */ + if ((gc->reg_dir_out || gc->reg_dir_in) && + !(flags & BGPIOF_UNREADABLE_REG_DIR)) { + if (gc->reg_dir_out) + gc->bgpio_dir = gc->read_reg(gc->reg_dir_out); + else if (gc->reg_dir_in) + gc->bgpio_dir = ~gc->read_reg(gc->reg_dir_in); + /* + * If we have two direction registers, synchronise + * input setting to output setting, the library + * can not handle a line being input and output at + * the same time. + */ + if (gc->reg_dir_out && gc->reg_dir_in) + gc->write_reg(gc->reg_dir_in, ~gc->bgpio_dir); + } + + return ret; +} +EXPORT_SYMBOL_GPL(bgpio_init); + +#if IS_ENABLED(CONFIG_GPIO_GENERIC_PLATFORM) + +static void __iomem *bgpio_map(struct platform_device *pdev, + const char *name, + resource_size_t sane_sz) +{ + struct resource *r; + resource_size_t sz; + + r = platform_get_resource_byname(pdev, IORESOURCE_MEM, name); + if (!r) + return NULL; + + sz = resource_size(r); + if (sz != sane_sz) + return IOMEM_ERR_PTR(-EINVAL); + + return devm_ioremap_resource(&pdev->dev, r); +} + +#ifdef CONFIG_OF +static const struct of_device_id bgpio_of_match[] = { + { .compatible = "brcm,bcm6345-gpio" }, + { .compatible = "wd,mbl-gpio" }, + { .compatible = "ni,169445-nand-gpio" }, + { } +}; +MODULE_DEVICE_TABLE(of, bgpio_of_match); + +static struct bgpio_pdata *bgpio_parse_dt(struct platform_device *pdev, + unsigned long *flags) +{ + struct bgpio_pdata *pdata; + + if (!of_match_device(bgpio_of_match, &pdev->dev)) + return NULL; + + pdata = devm_kzalloc(&pdev->dev, sizeof(struct bgpio_pdata), + GFP_KERNEL); + if (!pdata) + return ERR_PTR(-ENOMEM); + + pdata->base = -1; + + if (of_device_is_big_endian(pdev->dev.of_node)) + *flags |= BGPIOF_BIG_ENDIAN_BYTE_ORDER; + + if (of_property_read_bool(pdev->dev.of_node, "no-output")) + *flags |= BGPIOF_NO_OUTPUT; + + return pdata; +} +#else +static struct bgpio_pdata *bgpio_parse_dt(struct platform_device *pdev, + unsigned long *flags) +{ + return NULL; +} +#endif /* CONFIG_OF */ + +static int bgpio_pdev_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct resource *r; + void __iomem *dat; + void __iomem *set; + void __iomem *clr; + void __iomem *dirout; + void __iomem *dirin; + unsigned long sz; + unsigned long flags = 0; + int err; + struct gpio_chip *gc; + struct bgpio_pdata *pdata; + + pdata = bgpio_parse_dt(pdev, &flags); + if (IS_ERR(pdata)) + return PTR_ERR(pdata); + + if (!pdata) { + pdata = dev_get_platdata(dev); + flags = pdev->id_entry->driver_data; + } + + r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dat"); + if (!r) + return -EINVAL; + + sz = resource_size(r); + + dat = bgpio_map(pdev, "dat", sz); + if (IS_ERR(dat)) + return PTR_ERR(dat); + + set = bgpio_map(pdev, "set", sz); + if (IS_ERR(set)) + return PTR_ERR(set); + + clr = bgpio_map(pdev, "clr", sz); + if (IS_ERR(clr)) + return PTR_ERR(clr); + + dirout = bgpio_map(pdev, "dirout", sz); + if (IS_ERR(dirout)) + return PTR_ERR(dirout); + + dirin = bgpio_map(pdev, "dirin", sz); + if (IS_ERR(dirin)) + return PTR_ERR(dirin); + + gc = devm_kzalloc(&pdev->dev, sizeof(*gc), GFP_KERNEL); + if (!gc) + return -ENOMEM; + + err = bgpio_init(gc, dev, sz, dat, set, clr, dirout, dirin, flags); + if (err) + return err; + + if (pdata) { + if (pdata->label) + gc->label = pdata->label; + gc->base = pdata->base; + if (pdata->ngpio > 0) + gc->ngpio = pdata->ngpio; + } + + platform_set_drvdata(pdev, gc); + + return devm_gpiochip_add_data(&pdev->dev, gc, NULL); +} + +static const struct platform_device_id bgpio_id_table[] = { + { + .name = "basic-mmio-gpio", + .driver_data = 0, + }, { + .name = "basic-mmio-gpio-be", + .driver_data = BGPIOF_BIG_ENDIAN, + }, + { } +}; +MODULE_DEVICE_TABLE(platform, bgpio_id_table); + +static struct platform_driver bgpio_driver = { + .driver = { + .name = "basic-mmio-gpio", + .of_match_table = of_match_ptr(bgpio_of_match), + }, + .id_table = bgpio_id_table, + .probe = bgpio_pdev_probe, +}; + +module_platform_driver(bgpio_driver); + +#endif /* CONFIG_GPIO_GENERIC_PLATFORM */ + +MODULE_DESCRIPTION("Driver for basic memory-mapped GPIO controllers"); +MODULE_AUTHOR("Anton Vorontsov <cbouatmailru@gmail.com>"); +MODULE_LICENSE("GPL"); |